There is nothing wrong with Haskell. It's just that writing an IDE is a lot of work and nobody bothered to invest that work so far. Haskell for Mac changes that. (I'm biased — I wrote it.)
It definitely provides some optimism with what is possible in Haskell, nice! I think it might be more of a community thing, many Haskell researchers I know don't have a desire for IDEs (so they don't write or use them as much), but I would also chalk some of it up to the language design and evolution not being very accommodating to the goal.
I'm guessing it works by refreshing the world right now, correct?
