I am gonna have to agree with drivers being the big issue with Vista
I waited until SP1 for Vista came out. everything seems quite good(it was still smoother then 98 to xp was). Once everything was set to my liking, I got to gaming. crash..... try another game....crash.... many games still worked, but lots of them crashed in the most wonderful ways. Figuring damn you Vista, I was all ready to go back to XP.
Last shot was to try a different video card since other reported having similar issues. My old X1900XT in place and my 8800GTX out, all the sudden every game(I mean EVERY) worked for hours on end(with much worse performance mind you.). E-mailed Nvidia they said it was driver regression and to try a older driver.
Older drivers fixed some games and broke others. By this time, the 8800 series of card, while not old, where on a rather poor driver release schedule. It took over 9 months for a more stable driver to be released. Imagine that, 9 months even after Vista SP1 for a stable driver for a 500-600 dollar video card. I put that card into an XP system and picked up a 4870. Never had an issue with Vista again.
Now I am on 7, mostly since I just pass along my old computers as they are to others when I build a new one.
That said, Windows 7 is just a SP upgrade away from Vista on almost all levels.