A warning to all of my friends with iPhones: whenever you install an iOS update, make sure to have iTunes do a full backup of your phone before running the update. iTunes will not do the update for you automatically; you need to request it by clicking the button to backup the phone. And no, backing up to iCloud is not a full backup; you need to click the backup button in iTunes.
Luckily, I did the backup just before upgrading from iOS 6.1.1 to 6.1.2. I am so glad took the time to do the backup; 6.1.2 somehow borked my phone completely.