I did a bit of testing with Vista Ultimate x64, and after a _lot_ of tweaking, I managed to get it perfectly usable, although still noticably slower than XP.
The big advantage is that Vista's UI management is far more accelerated (ok, it's accelerated in another way) than the one in XP, resulting in a much smoother feel on high-end systems (notice the "high-end"? no rants please!), even though total system performance is lower.
If all you're doing is surfing the web, and writing letters, then this new feel to the UI is probably an advantage over XP, but for gamers, productivity users, and others who need to squeeze every last bit of powa out of their systems, then XP is probably a better choice, at least until we are forced to use Vista because of DX10 and newer versions of Windows live messenger. :lol:
