Well, sorry to necro this, but it's better than starting a new one.
So Vista has been final for a month now.
I've recently had the chance to upgrade my FS:SCP installation to the latest things (thanks taylor) and I have to say, it works flawlessly on vista with the very latest video card drivers. In fact, since nvidia had to redo their video card drivers, i actually think my openGL is better than it was before.
I had some serious problems running freespace on the late beta and RC1 builds, so I'm glad this cleared up nicely. I think most of the problem was the poor graphic card driver support during the beta process.