I wanted to try the new version of Unity that is under development for Ubuntu 12.04 LTS. I visited the page www.omgubuntu.co.uk that explains how to install it. So, it seems that you have to do the following:
sudo add-apt-repository ppa:unity-team/staging
sudo apt-get update && sudo apt-get dist-upgrade
After doing that I didn't notice any change. Did I miss something?