Apple already knows that iMessage, alone, is a huge selling point for their iPhones. They held out for a few years keeping iTunes away from the rest of us before finally giving in, but I very much doubt that they're going to open up iMessage any time soon. It's pretty much the only thing that keeps iPhone users in their ecosystem anymore.

That's true, but it would be more Applelike to develop their own app. They obviously know how to do it, then they could have 100% of the profits and not have to deal with a partner. But Tim Cook said they re not interested in doing anything like that.