deb http://ppa.launchpad.net/compiz/ubuntu hardy main
Close Software Sources and when prompted, choose to reload the repositories.
A number of software updates related to Compiz should become available now; install them using Update Manager. Log out and back in to Ubuntu or restart Compiz manually. You should now be up-to-date.
A nice new window shifter is available for the new Compiz called StackSwitch, just install it from the repo and disable the normal Shift Switcher. It would be nice if the author will add selecting the windows by the mouse much like Expo or some other window plugins.