What about non MS OS's. I'm starting to look into other OS rather than deal with upgrading to Vista.
Keep in mind that you'll have to learn the new OS and perhaps convert some documents to a format that works better with the new OS.
My recommencation is that, for any OS you decide to switch to, you upgrade on a new or different machine from your primary machine. A simple replacement of the OS on the old machine might not be so simple - you may have to worry about driver compatibility and OS performance requirements. A new machine, especially one that comes with the OS already installed, won't have as many troubles as older machines.
It would be great if it suppots other OSes, although honestly Windows tends to be the OS of choice for gamers.
If you're interested in at least trying to get any issues with emulation ironed out though, the beta is the time to do that.
My personal experience is that emulators and virtualizers have very poor support for 3D graphics. I think Wine has some support and VMWare has some experimental support. Virtual PC emulates an ancient S3 card that has no 3D acceleration at all. Supporting emulators could be pretty difficult.