It depends on how you see the future. Games, or rather top end games, in the future will need DirectX 10 which is only available in Vista click here
The issue with games and Vista is the need for adequate RAM and a good graphics card which is Directx compatible.
Some gamers have experienced a bit of a torrid ride as the graphics drivers were developed rather slowly. Things are much better now. So the answer is how do you see your own gaming needs?
as an OS I think Vista is great but I am no gamer.