It looks like it isn’t all wine and roses for iTunes 10: Among the complaints about the new icon, colorless interface and removal of 99-cent ringtone creation, a legitimate bug has surfaced between the media player and Automator.
In order to fix something, you need to break something ... or so the saying goes. Well, it appears as though that's what Apple has done with iTunes 9.2. The software, which was supposed to add support for iOS 4 and the iPhone 4 has appearently broken support for playing videos purchased from the iTunes Store.
There is a bug floating around that seems to be threatening users' data. When users start up their machines as normal, they seem to be finding themselves logged as a Guest on their machine and their files on their machine supposedly gone.
The App Store is sure to have its share of bugs, in fact, here’s one time-consuming App Store-update bug that could lead to severe frustration. Some users are logging into the iTunes Store to download app updates to find that they have an "outstanding balance." This predicament could leave users with buggy, partially downloaded software or just won't allow you to download the updates at all.
Fear not, it is probable that there is no outstanding balance (unless you're purposely trying to cheat the system). It seems the iTunes App Store belives you're trying to download applications without adequate credit available on your credit card when you select "Download All Free Updates." Downloading each App update, one at a time, should remedy the situation.
The idea behind the iTunes credit hold is tp keep users from downloading beyond their credit’s spending limit, but the bug can be annoying for users who just need their App updates.