Although Microsoft is saying that everybody should use Vista, I would say wait. Windows 7 is gonna be close enough to look like Vista without all the performance issues. To my knowledge you would only be waiting around a year.
They've ironed out the problems in Vista. It's getting better. Trust me, I used to hate it. I'm getting Windows 7 when it comes out. I'll build a new PC for it.
i was also wondering if i should get it or not. i have it on my laptop but its ok. i think im just going to go with xp sp3 i guess. i dont utilize all of the features very much, not my thing...wait
If you have money, you can get both. I don't think 7 will be perfect when it comes out. They will time just like they do with every other OS. I'll be waiting for service pack 1 on that as well.
I still need to get Vista. I'm just waiting for someone to tell me which one of the RAM's I chose is better. I just ordered a new case, power supply, and card. Why not upgrade the OS, as well?