iOS 7 Beta 6 is set to arrive next week. If rumors are accurate, this is the last beta before the Gold Master version releases.
Gold Master, for those who don’t know, is basically the version of iOS that consumers will see upon release. Unless anything horribly system-breaking happens, the Golden Master is the same version users will see as iOS 7 upon it’s public release.
That makes sense right now, because iOS 7 beta 6 is scheduled for next week. After that, GM should arrive in time for September 5th. Apple is scheduled to announce the next iPhone on September 10. The timing seems about right for a public release shortly after.