There is a programming language, B, which was superceded by C. Hence, the improvement to C was called C#. There’s also A, A#, D, E, F, and G. Oddly, there’s no F#, D# or G#, but there is an E#, which is kinda lame. Actually, there are two A#s: the .NET version of ADA, and the precursor to Aldor.
Au contraire: http://en.wikipedia.org/wiki/F_Sharp_(programming_language)
FWIW, a residual reason to pay attention to MSFT.
However, most folks in the field will gravitate in the Haskell direction.