Once we make clear that's not just for XB, but also, and probably more, for Windows Phone, this move makes a lot more sense, except for two things:
1) The price paid, Minecraft is big, but it already peaked, so it cannot be the magic bullet that will make Windows successful on phones and tablets, however it can at least help avoiding that the gap widen.
2) Mojang, and particularly its main product Minecraft, is essentially Notch, but MS didn't buy Notch, he sold Mojang to start again from a new smaller company that put less pressure on him.
Stwike him, Centuwion. Stwike him vewy wuffly! (Pontius Pilate, "Life of Brian")
A fart without stink is like a sky without stars.
TGS, Third Grade Shooter: brand new genre invented by Kevin Butler exclusively for Natal WiiToo Kinect. PEW! PEW-PEW-PEW!