IMO, the biggest benefit of Haskellis that it collects lots of programming language advancements that have been mostly ignored by the mainstream until recently.

IMO, the biggest benefit of Haskellis that it collects lots of programming language advancements that have been mostly ignored by the mainstream until recently. Haskell does generics really well, has some really cool abstraction facilities (leading to cool things like parser combinators, and a rich typeclass ecosystem) and the type system is really good at letting you write code that is correct if you manage to compile it. I think its still too early to say that Haskell gives immediate, quantifiable, benefits for multithreading but it sure gives more avenues to tame your code and lots of freedom for people to code different concurrency solutions on top of it.