I tired restoring. Did not work. Tried DFU restoring to iOS 7. The flickering decreased but is still present. Very strange. This flickering only appeared after I reset my iPhone in an attempt to counter horrible battery life. Currently, I am restoring back to iOS 6.1.4. I hate to say it but iOS 7 has been nothing of a nightmare. I downloaded iTunes 11.1 beta and then used the manual restore option to restore iOS 7 GM, effectively allowing me to install iOS 7 before the public launch. In theory, this should work fine as it's virtually the same build that will be available Wednesday. Anyway, besides horrible battery life (<4 hours) everything was OK until I restarted my phone and encountered this weird flickering. Before that I had restarted my phone other times but had no problems.