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I was unable to restore my iPhone after the update and my UDID is registered. Not too sure if its an iTunes issue or what, but it claimed my backup was corrupt. Though i was able to restore an ipod touch (iOS 6) using the iPhone backup without any issue.

So to answer your question, i have no idea.
 
You could possibly use something like iTools to manually put app data on for some specific apps. Don't quote me on this though.
 
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