A new Unity has been pushed into the Unity team’s PPA and we need testers to help give it a run for it’s money before it is accepted into Precise. Nick has all the details of how to participate in the testing right here. You will need to be running Precise to participate in the testing.
You can also find help if you get stuck in
#ubuntu-unity on Freenode. Happy testing!
I am running it now and the multi-monitor improvements in Precise are so much better than they used to be.