I'm a bit mixed on this, because this has the potential for disaster. On one hand, Microsoft become minecraft gods because of how well they manage it, on the other, they become the minecraft version of satan from how badly they Frick things up.
However, by doing this, they put a lot of risk on themselves. If they screw up, they will have thousands, perhaps millions, of really ticked off fans telling them off for ruining Minecraft. (Though, there's liable to be some for the simple fact that they might hate Microsoft.)