I've been using it this past week on various machines in various press rooms at CES and although I haven't had a chance really to play with it, I've liked what I've seen of it. Mind you, I've got a copy of Ultimate sitting at home just waiting for Nvidia to release RAID drivers, so it's not a financial decision for me. But even if it were, I think I'd go for it - it's a lovely OS.
And if you're a gamer - and you are, wolfie - you'll eventually want and need it for DirectX10, which promises to be awesome. I saw an early version of Crysis running at CES and even though it was buggy and running on a machine that was crashing for lack of adequate ventilation and stumbling along at 30-odd fps at a low res, believe me, it was stunning on Vista with DX10. Absolutely breathtaking. click here for a quick review of what I saw.