In recent years F# has been positioned as an optimised alternative to C# and F#'s scripting ability and IL compatibility with all Microsoft products have made it popular amongst developers.
In recent years, F# is placed as optimised alternative of C#, F#'s scripting ability and IL compitablility with all Microsoft products have made it popular amongst developers, many developers create solutions based on F# and expose the functionality using C# WCF Services.