Yeah, but I thought the GM is for developers only?
One thing we have learned this year is that we can forget about any pattern we thought we saw in the release cadences: Public beta initial release was "early", there was an unprecedented 3 week break between developer betas, there were 2 betas in one week and, finally, there is a public Golden Master release.
When you look at it, the public beta program is not even 2 years old. So its hard to say that there should have been any "pattern" at all. Pretty flimsy set of data points to do so. Looking back, it seems like the beta program has matured to such an extent that Apple felt comfortable getting the public involved earlier than last year (and that has been borne out by the relative stability of the beta releases in general). That comfort extended all the way to today, with Apple's decision to release the GM to the public - a first.