W8742xxxxxxx 20" 2.4 No crashes/freezes/artifacts ever with 10.4.10 / 1.1. Trying 1.2.1 now. http://www.apple.com/support/downloads/imacsoftwareupdate121tiger.html EDIT: Fast conclusion: The update didn't ruin what wasn't broken for me, it seems. I tried changing quick between screensaver, while having iPhoto running in the foreground, WoW in a window in the background -- all while spamming my cursor over the dock, magnifying it. I'm eager to hear other user's reports. I also would consider it wise to install this update, even though you haven't got any freezes, as this would help you notice a hardware problem earlier.