I have a Windows Nokia Lumia 920 and there are lots of users waiting for those amazing apps to come around. I think if a windows store version was created, lots of users would be interested.
I like the idea, but it seems Mojang has too much on their hands to make it for every app store there is. They are working on the PlayStation and Xbox versions which is already a lot for the small group developing them.
I suppose this could be done, but Mojang is pretty busy from the looks of it, on 1.8, the PlayStation and Xbox. Not to mention the new update for the pocket edition, which will just add more(like beetroot).