Let me start by saying that I hope I am wrong. I want a 3G iPhone and I want one now. That being said, it's not coming on 6/9.
First, this guy in the quote above has an incredibly strong point and it seems to have been mostly overlooked. There's no way the 2.0 firmware and appstore will be available as of the keynote on Tuesday. The SDK has to be final and developers need to test and submit their apps. Would Steve really tell everyone, "The 2.0 firmware is available now and the AppStore is open now! Go upgrade right now! Oh, by the way, there is nothing available at the AppStore yet. Give it a few weeks because we still need to give the developers the final SDK, there needs to be some testing, yada, yada, yada, apps should be available by the end of the month."
Second, AT&T has a freeze on vacation starting 6/15. Why would they allow everyone to go on vacation the week of the iPhone launch, then tell them they can't go on vacation starting the week after the launch?
Third, AT&T is hiring temps that start on 6/16. Why would they allow their employees to go on vacation the week of the iPhone launch, then require everyone to work, along with a group of temps, the second week of the release?
Third, if the new iPhone was to be released on Monday, they would have to arrive in the stores on Saturday or Monday morning at the very, very latest. That leaves no time to unbox the phones, receive them into the store's inventory, and have them ready for sale, let alone prep the staff (who's on vacation) of the features of the phone so they can answer customer questions.
Fourth, delivering boxes of new iPhones to the AT&T stores and Apple stores on Saturday or even early Monday morning would result in leaked photos, feature lists, etc. With all the hype for the new phone, it is incredibly unlikely that Apple is willing to ship the phones to the stores and just trust that all of those employees will follow the "DO NOT OPEN UNTIL STEVE SAYS SO DURING THE KEYNOTE on 6/9" stickers on the box.
Again, I hope I'm wrong. There's an AT&T store across the street from me at work. I'll be following the live blog of the keynote and if he announces they are immediately available I'll run over there, buy the phone, then go straight back to work and post here that I was wrong.