M$ also is a partner with Xenko. Xenko is a FULL C# game engine, not just scripting! If one even wanted to use F#, one wouldn’t require bindings since both languages are CLR based. This means you could always use the newest engine version. Sadly though, currently Xenko got some funky .Net hack which seem to break F#. But I’m positive that once .Net is more cross platform, this problem would get fixed, and anybody could use F# and Xenko without any hassle.
I observed on the Interwebz, that there is some growing grudge against OOP. And one of the solutions is functional programming. That’s why I mention F# here. I’ve been learning some F# during the last past month. And I understand now why its hype is so rock solid. For my current game in Unity, I use F# scripting. Finally I can work with game states without feeling like a weirdo. 