I'm using GHCJS and Reflex. Reflex is a recently released FRP library that makes a huge difference in one's ability to abstract GUI code. I personally feel that this combination of GHCJS + Reflex is the first thing I've used that makes web front end programming tolerable. A week ago there was a presentation about it at the NY Haskell Meetup. Look for videos of it to be posted early next week.
It's new, so not right now. But docs are coming. The NYHUG presentation will probably be the first thing along those lines. My company just rewrote a significant front-end app in it, so we clearly are invested in its future. In the meantime there's a #reflex-frp IRC channel on Freenode that you could use to talk to some of the people currently working with it.
