I never tried Vista --- too many horror stories. So I went straight from XP to Win 7.
I found the transition to be somewhat painful, mainly because Win 7 seems to have introduced yet another level of abstraction. Give me a street address and I'll find it. But you tell me to turn right at the fire hydrant, I'll get lost.
However, I must admit that my 3DMark06 scores are 10% higher on Win 7 than on XP (Dell M6300 Precision).
All that said, I do look forward to Win 7 RC.
Cheers
Bob