The IP argument seems a bit hollow to me, since Apple would've had to build probably upwards of 70% of the API surface for iOS just for their internal apps (and when they launched the iPhone SDK, they repeatedly pushed that developers were using the same tools they used to build the core apps). And even if that is true, the total cost of development of iOS is probably paid for by the sale of the devices. The phone is nothing without a way for someone to write software for it, whether it's Apple or a third-party.

I wonder how long until Apple finds the people who made the "you wouldn't steal a car" advertisement for the MPAA and gets them to make "you wouldn't offer your own payment method for digital goods".