Flash and Snow Leopard
Snow Leopard build 10A432 was seeded to eligible ADC members on August 12. If Apple had already declared build 10A432 the GM before seeding it to developers for testing, that would be completely irresponsible (though sadly, not unprecedented). In any case, if the 10A432 seed had turned up a show-stopping bug, Apple could have un-declared it GM. Is allowing an attacker to take control of a system via a web browser not a show-stopper?