I'm not saying it's the same for everyone but for those who experience freezes keep a eye out for this. Photobooth will definitely do it on my machine as well coverflow in iTunes, time machine, and even the intro to a video game. Soon as I open Photo booth or anything that has some strong animation (ie., coverflow or time machine, et al) I start seeing white artifacts streak randomly across the screen almost like getting static on ye'ole TV. Shortly thereafter a lockup is guarenteed to happen. May not be instant but it sure as heck does come within a short bit. Thoughts? **** EDIT **** Please include in your response if you notice the artifacts prior to the freezing. It's a simple thing to do. Try switching to a black or very dark background, open up photobooth, itunes, play a quicktime movie, a windowed video game, or time machine and see if you start seeing static type white artifacts. Continue and see if it locks up. So far since my last lockup I haven't had any issues. But that doesn't mean it won't happen. 50 bucks soon as I have a need to reboot it'll lock up. I'm trying to gather info. "my iMac locked up last night" doesn't help much.