C# is the most productive production language - it exposes a lot of functional conveniences along with the robustness of strong typing. And they're finally embracing the open source community - a huge plus.

#Language Features We use the basic syntax (for, foreach, if,while) and object oriented constructs (classes, very simple inheritance).

We also use lambdas and block methods extensively, an intermediate level programming construct, but in a very formulaic and predictable way.

PrometheanTV has used .NET and C# for several back-end applications and services including the Morphic Video Task System utilized to stream video assets to a variety of video delivery platforms including, Akamai, Brightcove, and others.

Unity3d builds the app and scripts are written in C#. It receives first class support from the Unity3d developer and most plugins exist in C# in comparison to Javascript (the other supported scripting language)

The main Carbonmade backend / API is written in C# and is ready to run on the CLR. We currently host on Windows but are preparing to migrate to Linux when the CoreCLR stabilizes.

originally used c# a decade ago when writing the tools for superman returns at my stint with electronic arts, have used it again recently for developing in unity.