There are quite a few hidden features of Leopard that will appeal to the Linux and Security geeks among us. One that’s particularly cool is that Leopard’s Mail.app finally includes IDLE support natively.

Nice.

So Apple recently put out this list of 300+ new features that are in Leopard. It’s a long list. Here’s my filtered collection of the most interesting stuff:

• UNIX® Certification. Mac OS X is now a fully certified UNIX operating system, conforming to both the Single UNIX Specification (SUSv3) and POSIX 1003.1. Deploy Leopard in environments that demand full UNIX conformance and enjoy expanded support for open standards popular in the UNIX community such as the OASIS Open Document Format (ODF) or ECMA’s Office XML.
• 64-Bit Applications. Make use of all your existing devices. Leopard is the first mainstream operating system to completely and seamlessly support both 32-bit and 64-bit applications on the same platform.
• Ruby on Rails. Work in a developer’s dreamland. Leopard is the perfect platform for Ruby on Rails development, with Rails, Mongrel, and Capistrano built in.
• Cocoa Bridges. Use Ruby and Python as first-class languages for building Cocoa applications, thanks to Objective-C bridges as well as full Xcode and Interface Builder support.
• Scripting Bridge. Use Objective-C, Ruby, and Python programs to automate Mac applications. The new Scripting Bridge enables them to easily generate AppleEvents using a concise, AppleScript-like syntax.
• AutoFS. Automatically mount and dismount network filesystems on separate threads to improve responsiveness and reliability.
• Multicore Optimized. Take full advantage of modern architectures with multiple processor cores with improved scheduling, memory management, and processor affinity algorithms.
• Application-Based Firewall. Gain more control over the built-in firewall. Specify the behavior of specific applications to either allow or block incoming connections.
• Stronger Encryption for Disk Images. Give your data even more security. Disk Utility now allows you to create encrypted disk images using 256-bit AES encryption.
• Application Sandboxing. Enjoy a higher level of protection. Sandboxing prevents hackers from hijacking applications to run their own code by making sure applications only do what they’re intended to do. It restricts an application’s file access, network access, and ability to launch other applications. Many Leopard applications — such as Bonjour, Quick Look, and the Spotlight indexer — are sandboxed so hackers can’t exploit them.
• Library Randomization. Defend against attackers with no effort at all. One of the most common security breaches occurs when a hacker’s code calls a known memory address to have a system function execute malicious code. Leopard frustrates this plan by relocating system libraries to one of several thousand possible randomly assigned addresses.
• Windows SMB Packet Signing. Enjoy improved compatibility and security with Windows-based servers.
• Streaming IO. Set up high-bandwidth data transfers in your applications, without having to worry about different hardware architectures and optimal caching strategies.
• DTrace. Monitor virtually any aspect of your application with DTrace, integrated into the Darwin kernel. Java, Ruby, Python, and Perl have also been extended to support DTrace, providing unprecedented access for monitoring the performance characteristics of those languages.
• Google Map Addresses. View a detailed map of any address in Address Book. Just hold down the Control key while clicking any address and select “Map of” and Safari will show you its location in Google Maps.
• Scriptable System Preferences & Applications. Do more with AppleScript. A number of system preferences in Leopard are now scriptable, including the Dock, Security, Exposé, Accounts, and Networking — as well as a number of features in iChat.
• Superior Error Messages. Determine the cause of script errors more easily with improved descriptive error reporting.
• Restore to Mac-Only Partition. Easily delete Windows and restore the disk space being used by the Windows partition back to Mac OS X.
• Stacks. Organize files in a neat stack on the Dock. One click and the stack springs open, revealing items in an elegant arc or an at-a-glance grid.
• Downloads Stack. Find your downloads quickly in one dedicated stack. Downloads from Safari, iChat, and Mail are automatically saved to the Downloads stack. Say goodbye to desktop clutter.
• Sorting Stacks. Order the files in your stacks any way you wish: by filename, date added, date modified, date created, or file type. Just Control-click the stack and pick an order.
• Finder’s New Sidebar. Use the sidebar to do even more. Now items are grouped into categories (places, devices, shared computers, and searches) just like the Source list in iTunes. Start finding what you want with a single click.
• Finder’s Cover Flow. Flip through your files in the Finder just like you flip through your album art in iTunes. Cover Flow displays the first page of every document. You can also click through multipage documents and play movies.
• Icon Preview. See files for what they really are. Leopard displays icons that are actual thumbnail previews of the documents themselves.
• Folder Sharing. Turn any folder on your Mac into a shared folder. You can share any folder in your home directory from the Sharing system preference. You can customize access privileges and even authorize specific contacts in your Address Book.
• Updated OpenGL. Run even the most up-to-date OpenGL-based applications that take advantage of the latest technologies.
• Improved iCal Interface. Enjoy a cleaner look that gets out of your way so you can focus on your calendars. The new iCal toolbar has the Leopard look, running across the top of the application window. The search bar is where you’d expect it, in the upper right corner.
• iCal Inline Editing. Effortlessly add attendees or change an event’s time directly on the event itself. The new Inline Inspector window appears when you double-click any event, making it faster and easier to change details on the fly.
• iCal Event Dropbox. Share the information you need for a successful meeting. Simply drag photos, video, or any kind of document into an event. Send email invitations to attendees and your attachments go along for the ride.
• iChat Screen Sharing. Collaborate with a buddy via iChat. Work on a Keynote presentation together, surf the web as a team, or help each other with an iMovie project. iChat initiates the connection (asking permission first) with an audio chat so you can talk things through as you work or play. Trade views of each other’s desktops. Even drag files from one computer to the other.
• iChat Invisibility. Change your status to “invisible” in iChat, and you won’t be seen by anyone. But you can still see the status of anyone on your buddy list.
• iChat AAC-LD Codec. Enjoy crystal-clear audio with AAC-LD compression technology. It combines the advantages of perceptual audio coding with low delay that’s optimal for real-time audio and video conferences.
• iChat Watch for My Name. Receive an alert when someone calls your name in a group chat. And never miss a comment directed to you.
• iChat SMS Forwarding. Register for AOL’s Mobile Forwarding service and receive instant messages on your phone when you’re away from your computer.
• iChat Tabbed Chat Windows. Consolidate your chat windows into a single tabbed window. Each chat is represented by a tab on the left side of the iChat window. Turning on tabbed chats is as easy as selecting “Collect chats into a single window” in iChat preferences.
• Network Scanning Support. Take advantage of new Bonjour-based network scanners, Leopard leads the way with the technology required to allow scanning over a network. (imaging, not security)
• Analysis Templates. Select one of the built-in Instruments templates to perform specific analysis tasks, or choose your own collection of instruments and save your layout as a custom template you can use again later.
• Create Instruments with DTrace. Monitor system activity from high-level application behavior down to the operating system kernel, all thanks to the power of DTrace and the instrument builder.
• Visual Analysis. Improve the performance of your applications by viewing the relationships between UI events and performance metrics such as CPU load, network and file activity, and memory usage.
• Forward as Attachment. Forward an email as an attachment instead of an inline message. Select the message or group of messages you’d like to forward and choose “Forward as Attachment” from the Message menu. You can also drag and drop Mail messages into applications like iChat and they’ll be sent as attachments.
• Mail Data Detectors. Act on information in Mail immediately. Mail automatically detects text fragments like appointments and addresses, and lets you choose smart actions with a click: create a new contact, map an address, or create an iCal event.
• Improved Mail Search. Find the right email at the top of the search results list, thanks to smarter relevance ranking in Spotlight. And everything you create in Mail — to-dos, notes, and, of course, email messages — appears in a Spotlight search of your system.
• Mail Photo Browser. Quickly and easily browse your entire iPhoto library to find the photo you need for your message.
• Simple Mail Setup. Automatically configure new email accounts. Just enter your email address and password. Mail knows the email settings for 30 leading email providers, including Yahoo!, AOL, Gmail, Verizon, AT&T, British Telecom, and Comcast.
• Self-Tuning TCP. Let Leopard adjust TCP buffer size automatically. Get optimum application performance, especially in high-bandwidth/high-latency environments.
• Dynamic Web Filter. Protect your children from websites with unsuitable content. Apple technology automatically trys to detect inappropriate content and prevents those web pages from appearing. You can override the filter by identifying sites you wish to explicitly allow or disallow certain websites.
• Activity Logging. Keep an eye on your children’s computer activities. Leopard logs websites visited and applications used. It also maintains a list of people who have chatted with your child using iChat and a transcript of each text chat session.
• New User Interface for Preview. Enjoy powerful new features wrapped in a simple and elegant user interface — striking the perfect balance between simplicity and capability.
• Improved PDF Annotations. Take advantage of new PDF annotations in Preview. Add Stickies-style notes and links to websites or other pages within the PDF. Mark important areas in ovals or rectangles and highlight text. All annotations are saved with the PDF so you can share them with others.
• Relevancy Ranked PDF Search. Harness the power of Spotlight. Preview now uses Spotlight to perform relevancy ranked searches on PDF documents, making it easier to find what you’re looking for.
• More Preview Image Manipulation Options. Edit your images in Preview. Crop, rotate, resize, and save images in a range of image formats. Selection tools make it a snap to cut and paste images from Preview directly into other applications.
• Preview Instant Alpha Background Removal. Easily remove the background from an image, leaving just the subject. Simply select Instant Alpha from the Tool Select button on the toolbar and click and drag in the area of the background you wish to remove. You can also use the Extract Shape tool to select a specific area of the image to keep, automatically excluding the rest.
• PDF Manipulation in Preview. Re-create your PDF as you like. Move individual pages around, or remove pages altogether. You can even combine PDFs with a simple drag and drop.
• Preview Batch Image Operations. Save time when rotating or resizing a group of images in Preview. Just click the thumbnails in the sidebar and you can change multiple images simultaneously.
• Preview GPS Metadata Support. Get real information from your photos. If your image has embedded GPS metadata, Preview will show you exactly where that perfect photo was taken. Open the Image inspector and select GPS. Preview pinpoints the location where you took the photo on a world map. From there you can even open the GPS location in Google Maps.
• Simplified Printing. Get the best-quality printouts with the least effort. The Print dialog is preconfigured for the most common print settings, while powerful presets optimize your settings without cluttering the screen with unused options. For most documents, simply click Print to produce great output.
• Location-Aware Printing. Print in multiple locations with ease. Leopard detects when you’ve changed locations. So as you move your Mac between work, school, and home, Mac OS X figures out which printer to use and sets it as the default printer. You can choose another printer whenever you want.
• CUPS v1.3. Tap the power of CUPS v1.3. It gives Mac OS X Leopard powerful print job spooling capabilities and enables CUPS-based printer driver development.
• Printer Drivers via Software Update. Make sure you always have the latest printer drivers. Download directly to your system using the familiar capabilities of Software Update.
• Quick Look. Look inside any document without launching an application. Use Quick Look with documents, images, songs, and movies and get a large-size preview of the file. Flip through multipage documents, preview movies, even add images to iPhoto. You can use Quick Look in Finder, Mail, and Time Machine.
• Enhanced Find in Safari. Instantly and graphically locate any text on the current web page. Safari highlights every instance of the word you’re searching for and even dims the rest of the page so you can focus on the results of your find.
• Pull Tab into New Window in Safari. Separate a tab into its own window with a simple drag and drop.
• Merge All Safari Windows. Combine all your open browser windows into one single, tabbed window.
• Preview Controls for PDFs. Gain new control over PDFs you see on the web. With Preview controls built into Safari, you can zoom in and out, navigate PDF pages with the sidebar, even open the PDF in a separate Preview window.
• Spaces. Organize your activities into separate spaces and easily switch from one to another. Make a space for work or play. Choose from a number of convenient options that make moving from space to space fast and easy.
• Search Shared Macs. Search any Mac on your network. Use Spotlight to find files just like you do on your Mac — by name, contents, or even metadata. You can search any connected Mac with Personal File Sharing enabled or a file server that’s sharing its files.
• Advanced Searches. Use a richer search vocabulary. The Spotlight search field now supports Boolean logic with AND/NOT/OR and parenthesis syntax. Search category labels such as “author” or “width.” Use ranges in your search including “greater than” and “less than.” Spotlight also understands quoted phrases and dates.
• Icon Mode in Open and Save Panels. View your files as icons in the Open and Save panels, just as you would in the Finder.
• Live Partition Resizing in Disk Utility. You may be able to gain disk space without losing data. If a volume is running out of space, simply delete the volume that comes after it on the disk and move the volume’s end point into the freed space.
• Guest Log-In Accounts. Allow anyone to surf the web and check email as a guest on your Mac. When they log out of the guest account, Mac OS X purges the account, removing any trace of their activity. So each time someone logs in as a guest, he or she gets a fresh, unused account.
• Grammar Check. Let your grammar set a shining example. A built-in English language grammar checker helps ensure that you don’t make errors in grammar.
• Advanced Account Customizations. Make changes to the user ID, login shell, and home directory for any account. Just hold down the Control key and click an account in the Accounts pane of System Preferences.
• Terminal Now Has Tabs. Combine all your open Terminal windows into a single window with multiple tabs. Rearrange your tabs with just a drag and drop. Change the order in which they appear or separate them out by pulling them into a separate window.
• Pull Terminal Tab into New Window. Separate a tab into its own window with a simple drag and drop.
• TextEdit Autosave. Ensure that your edits aren’t lost. Have TextEdit automatically save copies of your document at a specified time interval.
• OpenDocument and Word 2007 Formats in TextEdit. Take advantage of TextEdit support for the Word 2007 and OpenDocument formats for reading and writing.
• Back Up Everything. Automatic backup, built right into your Mac. Never worry about losing a file again. Time Machine stores an up-to-date copy of all your Mac’s files on an external hard drive, personal file sharing volume, or Mac OS X Server. That includes system files, applications, accounts, preferences, music, photos, movies, and documents.
• Go Back In Time. See what your computer looked like in the past. Select a specific date and let Time Machine find your most recent changes, or do a Spotlight search to find exactly the file you’re looking for. Once you do, click Restore and Time Machine brings it back to the present.
• Restore Your Mac. Restore everything on your Mac. Time Machine will put all the files right back where the originals were — as if nothing ever happened. You can even restore your files to set up a brand-new Mac.
• Browse Other Time Machine Disks. Browse other Time Machine disks with your Mac. Just plug in the drive and your Mac will recognize the Time Machine backup volume, even if it has backed up a different Mac.

According to Apple’s list of 300 new OS X features, Leopard has address space layout randomization.

A pleasant surprise.

OS X’s kernel isn’t strictly Unix-based. It’s called XNU, and it’s a monolithic (non micro) hybrid of both Mach And BSD kernel components. What’s quite interesting is how many people (including myself up until a little while ago) think that OS X has a pure Unix (BSD) kernel.

But that’s not the case. In fact, XNU is actually an acronym for “X is Not Unix”.

In other words, while Apple’s marketing team loves to play the Unix card at every turn, its developers explicitly made a distinction between the OS X’s kernel and a true Unix kernel.

Wikipedia goes on to mention, however, that this distinction will become far less dramatic in the event that OS X becomes POSIX compliant in Leopard.

…he was waiting for Microsoft to have their fun with Vista. Only then will they reveal what they’ve really been doing with Leopard. It’s like poker, you want to be the last one to act.

I expect a repeat of what happened with the iPod and the Zune:

Microsoft: And we present to you the Zune! Now with a wannabe iPod interface! Apple: LOL, we’re doing touch-screens, dumbass. Nice wheel, though…your idea?

So my thought is that Apple is waiting to spring another identical trap on Microsoft. Notice how quiet they’ve been about Leopard for all this time? Nothing at MacWorld — nothing since then. They’re letting Microsoft have its day because they know precisely what Vista has to offer. Steve has all the information and is basically setting them up for complete failure.

As soon as the buzz dies down from Vista, they’re doing to bust out with their equivalent of what the iPhone was to the Zune. In other words, something to make all the Microsoft fanboys who just bought Vista say, “Damn, I hate Apple…Why couldn’t Microsoft do that!?! I should have bought a Mac…”

I don’t know what Apple’s going to do with Leopard that’s going to make Vista look silly, but I have a very strong feeling it’s going to be something major in the UI arena. Hell, I just hope it involves replacing Finder.: