Notice the last clause in Section 2 :
(F) Platform Limitation- The licenses granted in sections 2(A) & 2(B) extend only to the software or derivative works that you create that run on a Microsoft Windows operating system product.
Wow. Can't believe that you can still get away with open-sourcing code and then choosing a license like that.
There's a great need for .NET application developers and consumers for them to be able to be cross-platform compatible - limiting yourself to a Windows environment limits your audience and adoption.
Hats off to Miguel and the Mono team for keeping Mono alive and well.