Well with the first version of the iPhone on ATT you paid FULL price. There was no subsidy. I also believe with the second version (3g) there was no non contract price so you had to sign a 2yr contract no matter what you paid for the phone subsidized or not if you did not qualify for an upgrade price.
I thought I remebered that they did either full price or subsudized price early on, adding the early upgrade price later. I got my iPhone 3G for the early upgrade price in November of 08.