Linux, typically, lags behind on new hardware, as compared to Microsoft, but, like Microsoft, there is usually a default driver for most of the absolutely needed things.
ATI is very bad about updating drivers for Linux. The two guys at NVidia, who do the drivers on their own, seem to keep those drivers up to date much better.
Odd. NVidia has no official support for Linux, but ATI does. Yet, NVidia does a better job than ATI.