Techpowerup reports AMD found that for some reason in-game anti-aliasing (AA) is disabled in Batman: Arkham Asylum when the game launcher detects an ATI GPU. Gamers with ATI GPUs can only use AA by forcing it in the Catalyst Control Center, but this results in reduced performance because the driver applies AA to every 3D object in the scene while the game engine uses it selectively.
It could be just an unfortunate bug, but as the new Batman game was developed under NVIDIA's The Way It's Meant To Be Played program some people believe it may be a dirty game from NVIDIA.
Developed under NVIDIA's The Way it's Meant to be Played program, and featuring NVIDIA's PhysX technology, the game's launcher disables in-game AA when it detects AMD's ATI Radeon graphics hardware. AMD's Ian McNaughton in his recent blog thread said that they had confirmed this by an experiment where they ran ATI Radeon hardware under changed device IDs. Says McNaughton: "Additionally, the in-game AA option was removed when ATI cards are detected. We were able to confirm this by changing the ids of ATI graphics cards in the Batman demo. By tricking the application, we were able to get in-game AA option where our performance was significantly enhanced." He further adds that the option is not available for the retail game as there is a secure-rom.