[rbanffy]

Microsoft is still the one leading .NET, defining what .NET is and what technologies it includes (and which it doesn't). While Mono is a nice subset that runs on non-Microsoft OSs, .NET is pretty much a Microsoft-centric technology.

You don't need to go further than the recent announcements and the excitement they generated among .NET users to see how dependent on Microsoft they are. It's Microsoft's show to run.