I have been using dwm for months now. Actually, I’ve been maintaining a fork of it, with patches that I like and such.
Being a lurker in #haskell I have been aware of the development of xmonad, which is a dwm-like window manager written in haskell. I tried xmonad a few months ago, and it was okay. It was missing some features of dwm that I thought I needed, like tags. I continued using dwm.
XMonad development has continued on, with many contributed extensions being added (including novel layout algorithms), and as of yesterday I decided to take the plunge and start using it.
So far, it requires a lot less changes to the config file to behave the way I want.
(Footnote: In fact, I first heard about dwm from Don Stewart, who is also one of the hackers behind xmonad.)