I have switched from Gnome to Mate, after playing with Cinnamon for a while. However, if you are a Gnome maniac not satisfied by the Gnome 3, you can switch to the old Classic Gnome (also called gnome-session-fallback), on your Ubuntu 12.04 “Precise Pangolin” Box.
Gnome Classic is still a viable solution for Ubuntu 12.04. Both the gnome-panel and indicator-applet-complete packages behind gnome-session-fallback are part of the Universe repository, so the community is responsable for the package’s integrity, not Canonical itself.
So, to install gnome-fallback, do this:
$ sudo apt-get install gnome-session-fallback
If you want to make the autologin to login to gnome-classic, do this:
For setting GNOME Classic with effects as default:
$ sudo /usr/lib/lightdm/lightdm-set-defaults -s gnome-classic
For setting GNOME Classic without effects as default:
sudo /usr/lib/lightdm/lightdm-set-defaults -s gnome-fallback