Imo, Vista is decent. When it first came out, it was crap. Same as Windows XP when it came out, if you remember.
But after lot's of updates it's o.k. now, but still not perfect.
I've had Windows 95, 98, 2000, XP, & now Vista.
But one bad thing about Vista, is that if you want it to run good, you have to tweak it... a lot. Especially if you want to play decent games, which I do a lot on my computer. And a lot of people aren't happy with that or do not know how to tweak it, so they just go ahead and stamp the "Reject" stamp on Vista. Which is what people did to XP years ago, haha. Ironic much?
In time, I think Vista can be improved, but you need a decent computer at the same time to be able to run Vista efficiently. It takes 1 GB just to run the program decently.