I'm speculating. I just can't see the financial upside for Apple to continue with Mac OS X. The vast majority of their sales and profits are from phones, tablets, and music.

Mac OS X and laptop and desktop hardware will become more and more of a distraction. We've seen them stagnating already. As a unix, Mac OS X is a rather elderly BSD.

They may keep a laptop device in the mix, but it will be more like a chromebook and run iOS.

Again, I'm speculating.