I experienced this using the latest ATI drivers and my on board HD3200 card. Even UI1 was messed up. I fell back to the Nvidia card, however, and now everything is fine. Would be interested to see why this happens. I know my problem was ATI, and would not have expected it from Nvidia, but still, I am pretty sure it is OpenGL and compositing related, and now that the newer chipsets are popping up on these new boards, Nvidia included, I guess we'll have to see how to get it resolved. I spent some time over the holidays playing with the xorg.conf file, and different versions of the ATI driver, but the result was always the same. I always fell back to my Nvidia 7200GS card before the next days production came on line. I will continue to test this, as the weeks progress, and I have also joined their forums to see if I can get any useful info there.
Best of luck to you.