Will Apple make Mac OS tablets??

So I've been pondering this for a while now, will Mac OS end up on a tablet, and/or a touch display MacBook/iMac, or does Apple see Mac OS as existing only on those tradition devices without the need for a touch interface?

Would this require a major overhaul of Mac OS?

Or even a completely different OS?

I have no double that Apple would be able to execute this well, I just wonder if they feel its the correct move to make?

Check out this video of Jeff Han at ted talks for some inspiration, if you haven't seen it already that is!