Just my $0.02...
Just my $0.02 US... Best guesses and wish list rolled together...
1. iTunes 4.9/5.0 demo... Will prob. show off the updated iPod sw (if it isn't fake) at the same time...
2. If the iTunes demo is late enough in the keynote, perhaps a "One more thing..." An ARM (Intel chip) or Cell based Auidio/Video device, iVod perhaps? A Tivo made to work like a Mac, take advantage of metadata (see a show you've recorded or ripped or bought on the iVideo Store, say "Learn more" and be shown a selection of websites w/ more info on that topic, or documents/bookmarks on the Macs in your home relating to that topic..) WiMax or 802.11n based Bonjour streaming of video/auido to other Macs running 10.4.2 or newer.. If Cell based, ability to play PS 1 and PS2 (can't imagine Sony would allow PS3) games... Built-in Bluetooth for remote and game controlers... I won't hold my breath, but this would be great..
3. AirPort updates... AirTunes now enabled for any sound source on your Mac: iTunes, iTivo/iVod, QuickTime, iPhoto, etc... Airport updated to 802.11n. 802.11n included in all iMac G5s, PowerBooks and G5 PowerMacs starting end of month... Built-in support in all AirPort sw for WiMax with Intel cards, support for WiMax via AirPort sw will work in 10.3 or 10.4... Again, not holding my breath, just major on my wish list...
4. MacOS X 10.4 optimized for use in PowerMacs equipped with the Cell as a coprocessor... drool.. sigh..wish, wish, not holding breath...
5. Xgrid for use with PS3... network your Macs with PS3 and offload any Xgrid enabled task (Video rendering, etc) to the Cell...Would be great to be able to use a PS3 to speed-up encoding in iLife and/or DVD Studio...
6. Dual-core Freescale G4 based PowerBooks, upgradeable PCI Express Graphics, HD res display, 802.11n built-in...
7. MacOS X Server for Intel x64... Possible.. This would allow Apple to sell more "Unlimited" licenses of MacOS X (A real bargain compared to M$ price range), and sell more Support packages... This would have nothing to do with any move to Intel across the board, rather, take an opportunity to get potential switchers from NT which is seeing it's support from M$ dwindle... This would allow MacOS X on Intel without requiring any 3rd parties to rewrite their sw.. (Servers have 90% of what customers will use on them out of the box, or am I wrong?) Won't compete with MacOS X on Macs, due to the price of MacOS X Server (Hint, not $129.99, still a deal compared to Windows Server offerings though.) ... Perhaps only offered on IBM or HP systems?
Just my thoughts and my wish list rolled together... It's WWDC, not MacWorld.. far-out ideas (things we may not see shipped right away) are always possible... 10.5 ideas, etc...