Originally Posted by solipsism
I asked an AT&T rep who stated that the $30/month data plan is required and the minimum voice plan is $40/month. She could be wrong, she is at the end of line when it comes to info but when I pressed her about my ability to upgrade my 2 EDGE iPhones she stated that she is not sure what AT&T will be doing as they have no stated a price for those not eligible upgrading yet, couldn't see Apple and AT&T screwing over their 2G iPhone users and losing out on the extra $10/month for data at the same time. She was very rational, but she is also going on pretty much the same limited intel as we are.
Upgrading the old iPhone to the iPhone 3G will be a lot easier from a logistical standpoint than will be upgrading the iPhone 3G to what's next. Because the original iPhone was not subsidized, AT&T made no investment that would have to be made up over the period of the two-year contract. With the iPhone 3G, AT&T is making an investment that will be made up in revenue from data plans over the period of the two-year contract. I'd say your chances of being able to upgrade your old iPhone are good, but once you have the 3G iPhone, you're stuck with it for two-years, unless of course AT&T offers an non-subsidized upgrade price.