I haven't figured out why this is happening because it seems to be random.
I'll be listening to music, adding music, syncing my iPod, etc. and iTunes will freeze. The music will still be playing and all other actions will still be performing, but I cannot see any of this. All I see is a frozen screen (either completely white or a "screenshot" of iTunes GUI). I can click and a song will play. All functions still work but I cannot see them.
This is true for most of the time, as far as I can tell. Sometimes, the application WILL crash after a little while. I'm not sure if it had the potential to do this every time it froze.
I first noticed this issue with the latest version 10.4.1 but the beta 10.5 also exhibits this issue. I am considering installing version 10.4.0 but I am doubtful that this will fix the problem.