If you are having a cold foot, asking yourself should I install or not install the Ubuntu Touch Preview? Well, this is how to install the Ubuntu touch preview on your Nexus 7, Nexus 10, Nexus 4 or Galaxy Nexus. Use this link for more detailed instructions and pictures. The Video below is a glance, and full preview of the Ubuntu Touch Developer Preview working on a Nexus Phone from OMG! Ubuntu. So if you are among the brave let us know your heart.
Source: OMG! Ubuntu