The devs are aware of a conflict with Cinnamon and the latest updates to Precise. Cinnamon for Precise has been removed from the PPA. They have cobbled together a patch and are testing now, according to something I read elsewhere. For now, you should remove Cinnamon from your system and be patient. I too, am waiting. Cinnamon looks like what I have been waiting for.
Update: the ppa has been updated for Precise.
I reinstalled the Cinnamon desktop to Ubuntu 12.04. It's still not perfect, but is working much better than the last experiment that I had with it.
Last edited by Gaspasser; 04-19-2012 at 09:02 PM.