Supposedly there's going to be some serious shader performance increases with the next patch. Gearbox says that they've been doing lots of work to create "fast shaders" that are supposed to give us something like a 30%-50% shader performance increase, which should be very nice if it makes it through Microsoft's hampster-powered quality control testing.
How happy is the blameless Vestal's lot!
The world forgetting, by the world forgot
Eternal sunshine of the spotless mind!
Each pray'r accepted, and each wish resign'd.