[objclxt]

Not to come off as uncaring, but I think you screwed yourself over if you installed the iOS 7 beta and didn't read the release notes.

iOS betas have always expired, going back years, and this has always been documented in the release notes. It's also made clear in the release notes that you can't upgrade via iTunes to the public release from a beta - you have to manually download the IPSW and update it yourself.

[bookface]

I was going to add a line at the end of my post saying that this was all, of course, my fault, but figured it went without saying. Lesson learned.