1.6 Ghz G5 across the line -- 533 mhz bus like the iMac. ATI Radeon 9600 with 64 MB VRAM.
G5s are nowhere near ready as are dual G4s. There will however be slight upgrades and price drops.
12" - upgrade to 1.5 Ghz G4, BT/AE built in (like the new iBooks), 80 GB HD, Mobility Radeon 9700 (64 MB) Price $1399
15" - upgrade to 1.67 Ghz G4, BT/AE built in, 80 GB, Backlit keyboard standard, Mobility Radeon 9800 (128 MB VRAM) Price - $2299
17" - Same as 15" except 17" display - $2599
-GREATLY improved performance
-New 'media tab' allowing easy access to photos, music and movies -- similar to how it is integrated in iDVD
Quicktime NG (next-gen)
First major change in the .mov format since QT 3. Integrated H.264, MP4, and Wavelet technology.
Support for .ogg, heAAC, and FLAC audio. (these will also be available for playback in new iTunes)
Apple is currently negotiating to get the full trailer for Episode III and the full trailer for Batman Begins to be released on keynote day -- to view would require download of NG.
New Pro key needed. Lower Price $19
"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.