It seems that yesterday developers got a hold of iOS 7 GM. Oddly’ we haven’t received it, but iOS 7 will be available soon enough.
That said, it looks like the Gold Master is available, and developers are making use of it in preparation for Apple’s official release on September 18th.
The GM is basically the consumer version of iOS 7. Unless there is anything system-breaking on the GM (there usually isn’t, as the major bugs have been squashed) this is the version we will all download next week as iOS 7.