I like iTunes. Never had any problems even on Windows machines. Just back up your iTunes libraries regularly and you should be fine. That could be said of any large application system though right?

My biggest gripe now is the Ping bar on the right hand side. It's taking up real estate in my iTunes frame and there is no easy way to get rid of it (yeah, I know there is a hack but subsequent updates from Apple restore it.) I wish there was an option to "Disable Ping" or "Hide Ping Bar".