I have just switched from Fluxbox to giving xmonad a go, and I am definitely liking it. However, the one thing I haven't managed to do is to change my desktop background.
I am using Ubuntu 8 (uh, can't remember the value after the point), and I installed xmonad through the package manager, and then ran xmonad from the list of environments available on the login screen.
I have tried setting it using gconftool as suggested on the Haskell wiki, but it doesn't seem to have any effect.