[Xichekolas]

Well said, but I don't think it's a problem per se. Lisp was way ahead of its time, but it also hung around until everyone caught up with it.

Programmers tend to think about code at the level of the most powerful language they know. Show someone partial application who has never used it and they say "that's a neat trick I guess", but take partial application away from someone that is used to it, and they suddenly feel like something vital is missing.

So at the moment, Haskell's new ideas seem at best to be "neat tricks" and at worst "confusing" to most programmers, but, as with Lisp, those ideas and features will get added to other more mainstream languages a bit at a time. Haskell's contribution probably won't happen because a bunch of people go out and learn Haskell, but because it's ideas will slowly move the cluster of mainstream languages up the curve.