Counter-Strike: Global Offensive is one of the few remaining titles from Valve that's highly sought after by Linux gamers but has yet to make its debut. Going back to last year we've known CS:GO has been running internally on Linux and even last April Intel Mesa developers have been optimizing their driver with CS:GO using their early access to the title in cooperation with Valve.
A few days ago another mainline Mesa commit happened that also benefits the Counter-Strike: Global Offensive performance on Linux. There was a patch merged that vectorizes multiple scalarassignments, which leads to reduced vertex shader instruction counts for some leading titles. Dota 2's vertex shader instruction count is down by 6.42%, L4D2 is down by 4.61%, and CS:GO's VS instruction count is down by 5.71%. Overall this 325 line patch leads to a reduction by about 3.27% of vertex shader instructions generated for affected programs.
The patch being talked about can be found via the Mesa Git viewer and will be part of the next Mesa release (likely to be known as Mesa 10.1).
Now let's hope Counter-Strike: Global Offensive finally makes it out soon for Linux gamers.