I installed vista on couple computers. Windows hasnt had such a huge makeover since windows 3 to win95. but all it did was copy modified GUI i already had from windowblinds.net and the abundance of other UI mod sites out there. even IE7 is a rip from Firefox.
finally got rid of vista today though. several programs not compatible at all, Adobe Premiere Elements and Nero 7 being the biggest for me, and several games. rarely crashed, no blue screens, but... ya its "beta" alright.
now windows 2007 Beta was good ;P so far anyway. Word/Excel and others all purrrty and GUI like Vista now