Apple has released iTunes 7.1 which is reported to include much needed fixes for the software to work properly on Windows Vista. I've not yet installed Vista, so personally I do not know what the problems were, but they are apparently fixed if you download the update.

Correction: While itunes 7.1 has fixed some minor problems with Vista, there is still a rather large buzzkill, there is still a possibility of your iPod becomming corrupted when ejected. There is also the issue of difficulties synchronizing Windows contacts. You can, however, transfer music & videos purchased from the iTunes music store to the iPod. Way to prioritize there, Apple. 

Download.