Just wanted to report a problem I experienced with the magiclantern-2011Jan28.550d.fw109.NoAudioMon.expo-settings.alex.zip build when reviewing photos/video. While going to the previous photo/video with the "<" button I was able to get my camera to freeze repeatedly. First time experiencing a freeze and was a unique feeling to turn the power switch off and have it do nothing. Quickly pulled the battery (gotta love the camera grip for making that easy). Was able to recreate a number of times.
If there is any better feedback/info/something I can do other than reporting this please let me know, I'm pretty new to this but happy to help in whatever way I can.