I don't know if it's magical or what, but my battery life has been longer since I did two things: 1. Registered my phone with iTunes via USB. 2. Opted to send anonymous data to Apple (forget what they officially say) I used my phone today as much or more as I had previously. Usually by the end of work, I'm at 20%. Today, I was at 69%. It was unbelievable. I had to do a double-take when I got home. Basically, I never put my phone into iTunes. I went the iCloud route. I had all betas on my 4, and haven't seen this good of battery life since iOS 4. I know those two things I listed seem random, but if you haven't tried them, give them a shot. Who knows... I'm not making this up.