During the week prior to the Starcraft II launch, performance results started surfacing showing a game easily playable, even with entry-level graphics cards. However, the results also showed ATI cards were not capable of supporting anti-aliasing in the game. This issue just got an answer though as ATI has released the 10.7a beta drivers.
These new beta drivers add support for anti-aliasing in Starcraft II through the ATI Catalyst Control Center, and are supported by all Windows based operating systems from XP to 7.
Additionally, the new drivers increase the performance of Quad CrossFireX configurations when using Eyefintiy. For full details, click on the source, where you can also grab the drivers.