The bits I'm really looking forward to in Snow Leopard.
From http://www.apple.com/macosx/refinements/enhancements-refinements.html
The Finder has been completely rewritten using Cocoa to take advantage of the new technologies in Snow Leopard, including 64-bit support and Grand Central Dispatch. It’s more responsive from top to bottom, with snappier performance throughout the Finder.
Snow Leopard makes ejecting external drives more reliable. Core system services such as Spotlight indexing and file system events will intelligently stop their work so you can remove your drive. And improved dialogs tell you which applications are using the drive so you know what to close in order to safely disconnect your drive.
Snow Leopard is up to 75 percent faster when shutting down, twice as fast when waking from sleep with screen locking enabled, and up to 55 percent faster at joining wireless networks.1
The AirPort item in the menu bar now includes signal strength for all available wireless networks, so you can see which access point has the best signal before selecting it.
Command-line users can now split their window into different terminal sessions, simplifying comparisons between activities.
iChat can now display iChat Theater content at higher resolution — up to 640 by 480 pixels, or four times the maximum resolution in Mac OS X Leopard.
The new QuickTime Player includes an elegant interface that puts the video you’re watching on center stage. Window and playback controls fade away, leaving just the high-quality video.
video decoding. QuickTime X accesses the H.264 video-decoding capabilities of the NVIDIA GeForce 9400M integrated graphics processor found in the many of the latest Mac computers. Using the GPU to decode video not only provides an fluid playback experience but frees the CPU for other tasks.
Catch the action taking place on your screen with screen recording. Start recording and QuickTime Player captures the activity on your screen and creates a movie file. It’s perfect for creating instructional media or when you need more than a simple screen shot.
Trim your media to the ideal length by removing unwanted portions from the beginning or end. Rather than relying on a simple timeline, QuickTime Player displays frame-based thumbnails that help you make the perfect edit.
Advanced artificial intelligence analyzes each PDF document to understand the structure of its words, paragraphs, columns, and visual layout and create a map of the document’s organization. Preview uses this information to help you accurately target the text you want to copy and paste, even if the text is in columns.
Mail now handles all your mail more quickly. It’s 85 percent faster to open your first viewable message, 3.5x faster to list the contents of a mailbox, 90 percent faster to search, and 2.3x faster to move messages.1
Dozens of small improvements in Mail make composing and editing HTML email messages more reliable.
iCal sets up your Gmail and Yahoo! calendars automatically. Just type in your address and password, and iCal configures your calendars.
In addition to per-meeting inspector windows, you can have a single inspector that displays the meeting information for the currently selected meeting. As you select different meetings, the inspector changes to show the appropriate meeting information.
for screen locking. If you set your Mac to require a password to wake from sleep, you can now add a delay of five seconds to four hours before the password is required.
Snow Leopard takes up less than half the disk space of the previous version, freeing about 6GB for you — enough for about 1,500 more songs or a few thousand more photos.6
Xcode has a new Build and Analyze operation to analyze code for correctness, point out errors with a Message Bubble, and draw graphical arrows alongside the code steps that can trigger the errors.
The Xcode user interface includes more natural code completion with improved suggestions, a unified build results window with a persistent log, refined Message Bubbles that wrap cleanly alongside the source code, easy access to recent projects on launch, and more.