I have to agree with this. I have an early 2011 13" MBP and as soon as I loaded the GM on I noticed the stuttery core graphics. All UI animations are significantly less fluid than under Lion which is a big surprise since I thought this was supposed to make things faster if anything (especially since Snow Leopard was faster than Lion). In any case it's the one disappointment for me with this release and I do hope Apple don't disregard it even though this is now "last gen" hardware. They do need to get better with testing and writing good drivers though. It seems to be a total crapshoot and since there's no way to change to other drivers (outside of downgrading) it's aggravating at times. For me, I've had an up and down experience with drivers since I got this machine with Snow Leopard all the way up to Mountain Lion now, but this is definitely the worst it's been. If I have more than a couple windows open and go into Mission Control it looks like it renders about 3 frames of the opening animation.