FYI, I've installed Whistler (WinXP beta 2) and AH. All is well. I get the same or a little better framerates that I got in ME and 2000. I was having problems running some games but once I upgraded to NVidia's 12.0 beta drivers all games are now working great. So far I'm very impressed with WinXP. It has a lot of cool added features and is VERY stable. If you're interested in getting the Release Candidates 1 & 2 you can go to Microsoft's page and send them $9.95, which will allow you to download the RC's when they are released.
http://www.microsoft.com/windowsxp/
