Been playing Angry Birds for a few days, no problem. Today I went into Menu/All Apps and... it was gone. Looked around a bit and couldn't find it, so I rebooted the phone. When I went back into the App list, it wasn't there - then briefly appeared for about 1/4 second and disappeared again. Fine, downloaded it again and it's back on the App list, complete with my existing levels. Anyone know what would have removed it from the app list?