I am not sure it will. However, it will be capable. By late 2015, I predict the OSX platform will mesh more with iOS and there might be a morphed iOSX which works on iPads but no iPhones.
The iPad will undoubtably become the main computer for a vast majority of the market. It will expand capability through ports or expansion docks or some other method. OSX will feed into it somehow. Don't expect to see a desktop like the current Macs to be on a pad until 2020 when the nm & battery technology become incredible.
I think Apple should be molding iMacs into iPads and MacPros within the next three years. Desktops are fading away, the iPads are getting more and more capable, but professional users still need something with high power to produce the works used by pads, pods, phones, and other devices.