IMHO the problem is with the graphics chip in all the 2011 MacBook Pros: 13, 15, and 17" alike. Go to any Apple store, go to any of the new Macs, run iPhoto and start a slide show. You will see tearing of the image on the top 5 - 15% of the screen. Its worst on the 17". Or just move any window back and forth rapidly near the top of the screen. Apple has yet to acknowledge the problem as of this writing. I feel like I'm in "the emporer has no clothes". Really just go to an Apple store, its very easy to reproduce the problem on any of the 2011 MacBook Pros. (not the white one though, and the Air is fine too). Then show it to the genius bar guy.   A friend of mine bought a 15" to show off his photos. He had to return it, and Apple was nice enough to give him his money back. All the Apple resellers and repair here in Taiwan know about this problem, but nobody can fix it. Apple has yet to acknowledge it, or fix it. Hopefully there's a software work-around. Replacing all those motherboards would be expensive. I suspect the Intel 3000 graphics chip, Intel has been trying to do graphics for 10 years, talking a big game but failing to deliver.  Its not the first time Apple has been burned on graphics. I guess they'll just have to make their own GPU's to go with their own CPU's. Someone suggested try disabling Quartz Extreme using Quartz Debug. I haven't tried it. Some more discussion here http://forums.macresource.com/read/1/1141003