I skipped it completely, win3, win95, win98, win98se, winXP Pro and may do the same for Vista.
We will have to wait some considerable time to see how Vista stacks up in that regard MS seem to be having a very hard time trying to kill XP (and failing) and now the big push for Windows 7 is about to commence. So Vista is almost the unloved middle child
I hate to say this, but there really isn't too much wrong with Vista. It's really getting a bad rap.
I've had it installed on a few machines, and the only real problem is poorly written software. The operating system itself is very nice, albeit a little hard to find things, but that's because we're still used to where everything was on all the previous os's. As long as you have a decent computer that's better than the minimum system requirements, and you do a fresh install (not an upgrade) it's actually not that bad.
I just hope that Windows 7 doesn't come out too soon, because my Vista cert will be worthless...