Currently Being ModeratedDec 19, 2011 3:21 PM (in response to perrygraph)
Trying to resolve the coverflow crash (crashing Music app, crashing the iPod) even when no music is playing, I finally told iTunes to not sync music and sync'd the iPod Touch 4th Gen, erasing all music from it. Then told iTunes to sync all the music and let the iPod Touch resync.
This resync did solve the problem of the blank Genius playlist.
This resync did not solve the coverflow crash problems, however.