Well, regarding Haskell, I completely agree, it takes some time and multiple resources to get going. Once you get the hang of it, you don't want to stop. As for clojure, @Stackprotector already asked me why I don't learn it,
so I guess it's on my list, although the description of it's relationship with haskell can be reversed:
Yes, Clojure is more dynamic (from what I know) and easier to pick up (from what I heard and can guess).
But if you already "got" Haskell, you might not want to switch, or at least the motivation is somewhat limited.
Maybe it's just a personal issue with my broken mind.