First of all, I can confirm the corrupted menus problem that is described here: http://devgurus.amd.com/thread/166553
I have also experienced this corruption sometimes in in-game menus (when the guardian of metal lets you choose some upgrades).
More annoying is the crash that I had twice now on different places on the Brütal Legends map. For no reason the screen goes dark (the last time there were dark grey vertical lines all over the screen). The sound keeps playing for some seconds, then the keyboard LEDs stop responding and the computer is frozen.
Here is my Xorg.0.log
Here are my system infos.
Please tell me if you need more information to fix the problem.