Currently running Mountain Lion after a failed time machine restore.
My days with beta OSes are over. I knew about bugs and all that, but completely breaking my install and not letting me roll back to the previous version sucks.
Which is why you should read the installation notes, which clearly tell you not to install beta software on primary machines or over the top of current operating systems, so you end up getting what you deserve. You never heard of installing on to a partition or external drive?