I've been using Vista since beta 2, and I wouldn't go back to XP pro for anything.
It does need a highish PC (I have a Core 2 1.86 and 2Gig RAM) but it's SO pretty
and MORE stable than XP.
The rest of my household is still on XP pro (four PCs) but only 'cause they don't wish to change.
(I also have two servers running Server 2003 SP2)
As for Linux...
Tried it a few times, with different releases.
But anything that needs me to fiddle to get it to run OK can lay there 'til it gets it right.
Those of you running Vista with 1Gig, try it with 2 (or more). You'll wonder why you didn't from the start.