Haha... tested with 1gb of ram.
Tests with more, I said this and linked in another thread with some poor comments made in return
SP1 for vista changes a few things and adds new features and the new DX update and ends up using even more resources, this may change since it is beta of the service pack but the fact that another beta sp3 for XP is actually running xp faster shows a bit of a funny turn there.
IF this holds water when both are officially released loads more will go back to xp I think
I still think MS Should bite the bullet and release dx10 for xp, would sell loads more games.