I'm running a partial upgrade of 12.04 to 12.10, but right now, if I choose to say 'yes' to 'sudo apt-get dist-upgrade'...
The following packages will be REMOVED: ubuntu-desktop unity ... The following packages will be upgraded: compiz compiz-core compiz-gnome compiz-plugins-default dkms evolution-data-server-common libcompizconfig0 libdecoration0
but if you do choose to remove unity in order to upgrade compiz, you can't re-install unity (I tried that).
also, the extra plugins are not available for me right now, so I am considering going back to 12.04 until things are sorted out in order to get the compiz features I miss.