I tried out Vista at the store I work at.
IMO?
Nice looking, but... no really big differences that would make me jump into Vista. I've heard about all the security features and so forth (something you can't really get into for the few minutes 'demoing' at a store) but, is it worth being 'virus free' while dealing with other bugs (not to mention the fact, it's virus free now. But for how long)?
Not to mention the fact that I already bought a new computer with XP. Yes, Vista ready, but do I really want to go through the hassle of backing up my stuff, reformatting my HD, and then installing Vista on it? <_<
Gaming wise? Well, most games I know work on XP. Vista? There are reports that so-and-so game... doesn't work on it. Now the big games I'm sure will work since, well, they better work given that I'm sure MS doesn't want to alienate those fans. But what about the more obscure games? And this computer, while it is powerful, it isn't THE most powerful computer either. So while games will look good on it, it won't look the best without some mishaps.
And again, given the possibility/probability of tons of bugs in it, any serious thoughts of an 'upgrade'... won't be for at least six months/one year.