A few months ago, we decided to write a big new software component at $work, basically a service layer that is going to accumulate lots of business logic. We discussed several programming languages, and thought that a statically typed language might be a good fit (we mostly did perl and python so far). C# was dismissed pretty quickly, because .Net was closed source, and Mono had the reputation of being a bit second rate (possibly not well-founded, but also hard to debunk for somebody not in the community).
I mentioned that Roslyn was also open source, but it was hard to convince anybody when the "main" implementation was still closed source (and we're very much an open + linux shop).
If this had come a year earlier, we might have picked C#. Maybe there'll be another project here in a few years...