The Financial Accounting Standards Board has forced Apple to reveal its financial statement in regards to how much money AT&T hands over for each iPhone activated. Gene Munster, an analyst at Piper Jaffray, has done the math and concluded that AT&T appears to be paying $18 a month, on average, to Apple for each iPhone activated on its network. That's $432 over a two year contract. Apple receives $831 for each iPhone it sells, a little less for iPhones sold in AT&T stores. I'm not surprised that Apple wants to maintain its exclusive deal with AT&T rather than to sell unlocked phones or cut deals with multiple carriers.
News source: New York Times Blog