Minecraft the next big software platform?

The last few days in software has been interesting. In fact the last couple of weeks have been strange. And that's just in the Minecraft community alone.
Lets recap:
Few days ago Mojang makers of Minecraft was "officially" bought by Microsoft.
Couple of weeks ago, CraftBukkit hit major issues, DMCA of its code base and all.
So many people have left the bukkit universe that it probably won't be restarted.

Now this is a little away from what I normally post, but it fits in I think. Because why does Microsoft want Mojang?
Is it for the staff? Software? Or is it for its user base.
Now at this point no official response from Microsoft has occurred so this is all just speculation.

My personal belief is Microsoft wants Minecraft for its user base. It is to promote its mobile platform as well as its gaming platform.
Now this leads a lot of possibilities.

Microsoft doesn't like Java they want c++ and c#. But the pc version is in Java. They will certainly not want to stop supporting Mac OSX and Linux.

So what could their options be at this point.

1. Rewrite pc Minecraft in e.g. c#
2. Write a java compiler for CLR
3. Use the Xbox version of Minecraft as a base for the pc version

Now each of these things has its pros and cons.

Rewriting would probably mean better performance. But to get good cross platform support it would have to be tested upon Mono.

There is already Java compilers for CLR so its not crazy, Microsoft could freely buy one up and take over. Make it official part of Visual Studio fairly easily.

Lastly use the Xbox version. This is probably the less likely choice. Almost no modding potential and doesn't currently run on Windows let alone Linux.

Note I am ignoring the most obvious answer keep it in Java and do nothing. For licensing reasons and for company culture I believe they will not.

That's interesting and all for the source code, but what will they do with the source once they have it?
Well its actually quite questionable really. Based upon their handling of .net I believe they will heavily believe in open sourcing it with Microsoft still owning and controlling it.
But why am I taking this route, its a commercial product after all?

Because Microsoft view it as a platform. Not as a product per say.
The platform is to get people into their devices, software tool chain. They want people to learn c# not Java.
They want people to buy Visual Studio. I think you get the drift.

So modding support will be a clear yes in terms of support. But we may just loose the Java part of Minecraft pc version completely.
But on the plus side it'll be far more transparent and easier to do! Probably with official tutorials and everything.

It's going to be an interesting time in the next year or so.