I like vista, but have a few issues with it:

ATI Radeon driver keeps switching back to the MS one.
Audio clicks, pops and stutters (I'll put this down to drivers for the minute as I am using ones meant for XP)
Remote assistance does not allow me to help an XP-SP2 client, complains of wrong version!
Glass disables when you make wmp full screen (multi-mon)
Excessive hard dis activity, like _all_ the time, even when I am not using it (its not swapping, I have plenty of ram)