I went to CUFP this year. I've been diving into Haskell the last year and I thought it would be interesting to see how Haskell (and functional programming in general) were being used.

A couple of quick thoughts:

1. Enjoyed the tutorial on "High Performance Haskell" (slides here). I've spent the last year learning about Haskell but I'm not completely comfortable with it yet. The level of this tutorial was just about right. None of the stuff was over my head.

2. F# shows a lot of promise. I don't use any MS developer products but I'm considering getting Visual Studio to try out F#. It looks like a functional programming language with the fit and polish of the mainstream programming languages e.g. Java, C#

3. Side effects, imperative style are not optimal but sometimes they are very useful. This was a comment that was made in different forms over various talks. It surprised me a little but it shouldn't have. Haskell has affected my day to day work by making me more mindful about side effects. Perhaps that is the biggest thing functional programming can teach working programmers, to understand the various trade offs you make when you apply the different programming language paradigms (functional, imperative, oo).

4. Lots of people appear to be using Scala, Erlang and Ocaml to do serious work even if they're not blogging about it.

5. Not much was said about Clojure. This was a little surprising. 

Overall, it was a worthwhile two days and I learnt a lot. Still digesting the conference material and will be doing that for awhile.