Today at DesignerUtopia I was fortunate enough to sit in on the session delivered by Tjeerd Hoek, User Experience Design Director on Windows Vista.
One of the interesting things he talked about was how they collected feedback from families using good or bad smiley faces in system tray where they could tell us about good and bad experiences they came across.
Glass is in there not for the sake of glass but to reduce the visual distractions from the user's tasks and what they are trying to achieve.
He described the Aero interface as -
Tip from Tjeerd - Try searching in explorer and then pressing down arrow to select a search result, you can go right down thru your search result set - nice!
Check out the Windows Vista User Experience Guidelines to find out more details on how and why Vista looks and feels like it does :-)
Download details- Windows Vista User Experience Guidelines