I upgraded yesterday simply because I use Exchange calendars, so better battery life was worth the hassle. I'm not going to bother with my iPad, since its battery life is amazing and there's no real reason to worry about the upgrade there, so I'll stay on 6.1. Wasn't too bad, though. I bought PkgBackup to back up all my Cydia stuff, did an iTunes backup, restored, Jailbroke, restored my iTunes backup, then restored my PkgBackup, and my phone was exactly how I had it before the upgrade. The only thing that's a pain is that it just takes quite a while. The iTunes restore, including all app syncing, took about an hour and a half, and my PkgBackup restore took another 45 minutes or so, plus the time to make the backups, etc. Still, not a whole lot of interaction, just that the phone was out of commission for about 4 hours total.