Don't know if this got lost in the other thread about flickering for those users who have CrossfireX or SLi, but for CrossfireX at least, AMD have releases a new set of profiles to fix just that...
Direct File:
http://www2.ati.com/drivers/hotfix/catalyst_application_profiles/amd_catalyst_11.3_cap1.exe
It has got rid of the flickering I was getting before (Dual Radeon HD 5770's) - Game barely still breaks 30FPS as an average when everything's set to "Extreme" @ 1920 X 1200 res. Oh well, now lets bring on the optimisations!
Oh yeah, this patch is only for users of the Steam version.