Look at your macbook/computer screen- try touching the icons, dragging windows, etc. with your hands. In about 45 seconds, your arms will start getting tired. This is because a) your using your arm muscles actively (you don't when just type on a keyboard or use a mouse) and your arms are above your heart- making it harder for the blood to be pumped in your arms.
Apple engineers are aware of this simple fact, and this is the reason for which we will never have a touch iMac or a touch macbook.
In addition, I highly doubt Apple would release touch based computers running OS X. There's a simple reason to that- OS X was designed with the idea of a mouse in mind, not a touch interface.
As a result, if we are to see "macbook touch" or "macbook tablet", it will very probably be in the "ipad" form factor, and with OS 11- which won't be before a handful of years.