Download one of the free demo versions and try it yourself. It has most of the annoyances that Vista does, it's just a bit more polished in places. The one thing I have honestly noticed (on newer hardware and software) is that it actually seems to behave a bit more reliably than XP, which sort of suggests that hard/software makers are starting to give Vista/Win7 their priority over XP, and when that happens it's probably a good time to start thinking about switching.
There's a few things I don't like about Windows 7 though - Nvidia's drivers have more functions on XP than they do on Windows 7, I acually switched the new bar behaviour off and put it back to the old quick launch style bar, I prefer the old XP style search even if it's supposed to be better on Win7, it still eats more memory and is slower in places than XP, and UAC is still obnoxious.. But with better support for new hardware I think it's something we'll all be stuck with eventually..