Mono is widely used in games for Linux, for what it's worth. A lot of independent games have been written in the .NET XNA framework, and Mono has a Monogame com

Mono is widely used in games for Linux, for what it's worth. A lot of independent games have been written in the .NET XNA framework, and Mono has a Monogame component that allows developers to port these games to Linux relatively easily. Between the Humble Bundles including a lot of Linux ports and the Linux Steam/Steam OS launch from Valve, there's a lot of these ports coming out right now.