It seems to be dead. Is it?
If it is, what should I use instead?
gtk2hs is very much alive... I think it's too early to announce wxhaskell's demise, yet. Hackage says the May version builds fine with ghc7, there might be other reasons there hasn't been an update.
...unless, of course, you're looking for more haskelly approaches to GUI like grapefruit, none of which are really ready for prime time, though, due to the general epicness of getting FRP right.