Mac OS X 10.8 vs. Ubuntu 12.04 LTS Performance
When starting with the OpenArena game that is native to both platforms, Mac OS X 10.8 was not any faster than OS X 10.7.3 with the Intel Sandy Bridge HD 3000 graphics. However, the latest Mac OS X and its Intel graphics drivers were faster than the Ubuntu 12.04 LTS stock experience with Linux 3.2 and Mesa 8.0. Mountain Lion was about 34% faster for this OpenGL game at 1920 x 1080 than the Precise Pangolin. At least Ubuntu 12.04 LTS was better than the still a bit buggy Ubuntu 11.10 experience.
Mac OS X was also much faster with Nexuiz than was Ubuntu Linux on Intel Sandy Bridge hardware, but to the order of 2.5x faster.
Warsow on Mac OS X 10.8 Developer Preview 1 was more than twice as fast as Ubuntu 11.10.