I truly think when the time comes to get the iPhone, they will let you get it for the $399/$499 pricing, regardless of what the retarded ATT eligibility system says right now. None of the customer service reps at ATT know what the hell they're talking about and they're system is too complicated for them to explain any of it to you. They just look at the system and say "oh, looks like you're not eligible."
I've talked to 3 Apple people, and they all said if you're not eligible for the 199/299 pricing, then everyone should be eligible for the 399/499 early upgrade pricing. And if you argue your reasoning to the Apple store with the document that clearly states all other iPhone owners are eligible for the early upgrade price, I think they'll let you go with that pricing. They allowed it last year, and there's no reason it shouldn't be this year, especially when someone who has the same phone, got it at the same time, and pay the same monthly gets the full subsidized price, while others are stuck at full retail.
All that being said, I am still willing to pay $599/699. My plan is to argue until I get the 399/499 pricing, but if they don't budge I will probably just buy it full retail because I don't have to extend my contract. I have a year left, so at that point, I can sell the iPhone 4 and get the next upgrade at full subsidized pricing...or even have the option to switch carriers, if that ever happens. For me, because I like to upgrade every year, it doesn't make a difference to me. I can pay 599/699 right now, and pay 199/299 next year.. or I will pay 399/499 now and pay 399/499 next year for the early upgrade.