I just tried integrating xmonad with GNOME on Ubuntu 10.04, according to the instructions found here: http://www.haskell.org/haskellwiki/Xmonad/Using_xmonad_in_Gnome#Ubuntu_Karmic
Unfortunately, I was not successful at getting it to work. I'm wondering are there any tiling window managers that are easy to install and use inside of GNOME as a replacement for Metacity or Compiz?
Update I just got xmonad working inside of GNOME. This was a two-step process:
First, execute this line inside of GNOME:
gconftool-2 -s /desktop/gnome/session/required_components/windowmanager xmonad --type string
Second, and most critically (this was the step I was missing), add the following to ~/.xmonad/xmonad.hs:
import XMonad import XMonad.Config.Gnome main = xmonad gnomeConfig
As described here: http://xmonad.org/xmonad-docs/xmonad-contrib/XMonad-Config-Gnome.html