The thing I would like to know is if the update CD will be available some days after the complete OSX, or a couple of weeks. I don't know if I would wait so long, given that postal delays are sometimes very long (4 to 5 weeks !).
It would be nicer if Apple registered the people who would like to have the update (on the AppleStore for exemple), and make it be available through mail by the end of the month of September, like they did for the 10.0. I received the system by mail only 2 days after the official launch, so do it again Apple !