> Apple will sell $5B in apps this year and make $1.5B from their 30% stake. Almost pure profit, as the App Store can't cost more than $100M to operate. In fact, the marketing of the App Store is probably 10x the cost of running it (someone in advertising please fact check my ass on that one).
It has been widely suspected that the App Store and iTunes are loss-leaders for Apple. The company itself has reported that it ekes out a profit from those divisions. The App Store and iTunes exist to sell iOS devices and Macs.
A payments API makes sense just like the in-app purchases API does. This is a lot of hand-waving for something that has probably always been on the table.