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This is typical for the first day of updates, nothing is wrong with the iPhone - it's just Apple having a hard time with the load.

I just updated my friend's iPhone - and had to try about a dozen times before the download began. Once the download began, ran into an error twice. Just keep trying… third time was the lock-in and now it's all working well.

I tell ya, the biggest surprise for me in this update is how many apps took advantage of this launch to completely revamp their apps for iOS API's and the looks and feel! Amazing amount of excellent updates… now that iOS 7 is official, that fact alone surpasses all of iOS 7 for me. =)
 
Mine's going through now..... took me about 3hrs and 45 attempts but I've got progress. I guess you've got to expect congestion with the sheer number of people trying to update at once.
 
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