Will it run OS X or iOS?
If iOS, what difference is a MacBook over an iPad Pro with a keyboard?
If OS X, how will it perform when it needs to emulate native OS X apps?
I’d say it would run neither. Why couldn’t it be a custom design? And I think if they think they can nail it like they did with iPhone why keep those iPads anymore. They could simply do their marketing trick (and they are insanely good at it) and in a couple of years we will forget PCs and tablets like we did Nokia. It’s a thought...