I don't mean to knock Haskell at all. It's a fine language with a great community around it.

That said, the number of commercial applications developed in Haskell is very small, because, I think, it doesn't integrate as well into the larger ecosystems around it. It seems like it's a beautiful island all by itself.

The number of commercial applications developed in functional programming languages as a whole is pretty small compared to mainstream languages. I am a dotnet dev and also like F# a lot, but I cannot think of very many commercial applications written in F# either.

That's true, but for someone like me in a C# shop, I can slip F# code into our apps seamlessly. No one would say the apps are written in F#, but several key components are.

Hopefully, FP will take over the world soon and Haskell and F# will both be at the top of the charts! :)

yeah, very cool you were able to find a way to write some F# at work, I wish I could too.

Given trends, I don't expect to see any exponential growth though.