Gusty Upgrade
I just upgraded to Ubuntu Gusty a few days ago... This prompted me to play with new window managers and I'm very much impressed with the work that has been done with XFCE (4.4.1 is the version of my panel). It is lightweight and does everything that I need to get done with a window manager with a very small memory footprint. This window manager and my little dual core toshiba is meaning a very fast and stable setup.