Apple just released the new iOS 7 Beta 6 revision to developers earlier this morning. Unlike previous releases, Beta 6 came a bit earlier than the usual 2 weeks. Apple iOS Developer Center pointed out that iOS 7 Beta 6 fixes an iTunes bug which causes media files to play or download without any user interaction.
The new iOS 7 Beta 6 has a version number of 11A4449d, whereas the previous iOS 7 Beta 5 had 11A4449a. The update size of iOS 7 beta 6 on iPhone 5 is only 13.5MB and it should be a minor release solving some bugs on the new OS.