• Fixing nested sorting in dock stacks, which was fine in Leopard but got broken in Snow Leopard.
• Full GUI implementation of some of the hidden defaults write preferences, for instance the very useful recent items stack, the 'new list view' mode for stacks and quicklook xray folders in Finder.
• Decent SMB browsing straight out of the box rather than 10 months later as it was with Leopard and is hopefully going to not be longer than in SL.
• Feature parity with Finder in open/save dialogs - sort options for column view mode, ability to rename files, etc., and options more obviously visible, like the options for icon view that are -only- available by click and hold, not right-click or anything, and not obvious at all given that those appear to be just buttons.
• Ability to set default size & position for all new Finder windows regardless of path - Windows 7 got this done and it's really nice there and something I've wanted since 10.1.
• Expanded Dock options - the MS Office apps have 'recent items' accessible right from the dock icon; Apple should implement that for all appropriate apps and make it accessible even when the apps are not open, à la Windows 7 superbar, which does a good job of this except that it puts the most recent item furthest away in the list!
• Dashboard overhaul - or indeed just removing it altogether. Get rid of the iTunes widget crashes that have survived almost 6 years of updates; make more built-in widgets useful outside the US; upskill the calculator, calendar and clock ... or, again, just remove it altogether.
• QuickTime overhaul #2 - give us back the old 'pro' features without needing two versions installed. Better video screen capture including of an external display.
• Ongoing improvement in Preview - it has come a long way especially with annotations but could really benefit from just straight up MS Paint like capabilities; this is still a big part of the picture (no pun) missing from OS X, and again something I've wanted since 10.1.
• Improvements in Boot camp so that you can turn off keyboard backlighting, and so that the time sets correctly between restarts, and better support for mighty/magic mouse in Windows especially with horizontal scrolling.
• Better syncing between Mail.app and Mail on iPhone, so that Mail.app correctly shows that I replied to messages from my iPhone.
• Stopping the bluetooth menu extra appearing and sticking around when a device hits low battery - just a warning will do thanks.
• Support for saving plain text with Windows line-endings from TextEdit. Yet another thing I've wanted since 10.1! AppleScript editor can do it happily and has less need to as far as I can see.
• Ongoing improvements in networking, security, firewall settings, etc. Vista made networking 'just work' and OS X should be able to do the same.
And yep, I'd buy that

.