I'm not an artist, so this is very much coder cut-n-paste...
I think Apple are moving to the smoothed rectangles style shown by the Cube, iBook 2001 and TiBook. The cool technology is that the ultra flat TFT screen has no back. It's a transparent glass/LCD/glass wafer that pulls up as the lid of the Glass Mac. Because there isn't a heavy duty backlight (backlights lose 90% of the light they try to push through an LCD), the GlassMac will use very little energy above that required for its G3/G4 processor.
Apple will also jump the audio from USB to Firewire (there are already extreme hi-fi manufacturers making Firewire speakers) and Airburst will be bundled with all of them (If only!).