It's great to see everyone with XP say "vista is teh bugz" and everyone with Vista say "XP is teh old".
I'm no expert, but I've had this computer with Vista for about 6 months, and had XP for 3 years prior.
People said it would be slow, it is not. I have yet to experience any form of lag when running high-performance programs, like Crysis for example. And I don't even have maximized gear. Vista works just as fast on top of the line hardware as XP do.
People said it would be buggy. I haven't had a single crash or a single problem with bugs. If you take care of your computer, XP or Vista doesn't matter, none of them will have major flaws.
People said it would be incompatible. Once again, I have games and programs from most generations and none of them has suffered problems running or installing.
Now, does Vista look better? Yes it does, Aero is much more beautiful and pleasant.
Does Vista have any features XP don't? A few, none major. But I like being able to turn down volume for separate programs in the mixer for example. Small things add up, and Vista has a lot of small things XP don't.
Is Vista probably a better choice for the future, considering it is the latest shit? Yes.
I think most people who bash Vista are just jumping on the bandwagon and haven't even used it. XP was a precious OS, but Vista is better. Otherwise it would never had been released.
EDIT:
One thing though! Vista has a really annoying feature from the start which prevents you from being true administrator of the computer on your account. But that took me about 3 minutes to fix, and it wasn't a big deal.