For both Microsoft and Apple this presents major challenges.
Microsoft are desperately trying to reform their business away from desktops and laptops with more tablet friendly Windows 8 and RT. There's no doubting that they still have a long road to travel before achieving any success in this arena. Windows Phone, the third leg of its strategy has taken more than two years to reach third position in the mobile platform race, and even that is more a result of the collapse of Blackberry and the death of Symbian.
Apple meanwhile has edged some of its iOS features into Mac OS, without really changing the way that OS X works. Will we see a touchscreen MacBook in the future? Well Apple were recently awarded a patent for a Transformer Prime-like device that used wireless charging to keep the tablet component in a state of readiness; so it would seem that the company are at least considering their options.
Would a laptop touch hybrid from Apple use OS X or iOS though? Whichever option Apple chooses there would be work to be done to deliver the sort of experience which Apple is famous for.
Either way Apple needs to address the question quickly, as Microsoft and its partners (and let's not forget Google, who are looking to compete in the same space) begin to produce devices that make more sense than having an iPad and a MacBook.