I got very excited by Haskell about 18 months ago and spent a fair amount of time kicking the tires and reading the Haskell book. That said, my interest waned and I moved on to other things (mostly Ruby development with some Clojure, less Scala).
When I noticed the the recent new Haskell release for July 2010 I installed it and started working through Miran Lipovača's online book Learn You a Haskell for Great Good!. This time, things seem to "just click" and Haskell's functional style seems very natural. I have real regrets that I probably won't be using Haskell much because I mostly code in what people pay me to use which in the last 5 years has been Lisp, Ruby, Java, and Clojure.