XP was my primary OS until May 5th (7 RC release).
I'm now using 7 on my netbook (asus EEE 1000HE) and my desktop.
It feels like a real upgrade, sort of like going from Windows 3.1 to Win95.
I thought that Vista eventually was an OK OS, although still slow and bloated, once they worked out the bugs.
I think they have a winner here with Win 7 (and it is really Windows 6.1). Good performance, and some things even seem to work better than they did under XP.