How To Auto Login To Gnome In Ubuntu 11.10
Ubuntu 11.10 came with Unity as the default login session (including both 2D and 3D), while users are given the option to install Gnome 3 from official Ubuntu repositories. Many Gnome 3 users are finding it hard to make Gnome the default login session. This is because, normally, one can disable auto login from Unity, and then enable it after logging into the Gnome session (to make Gnome the default login session). However, this method is not working for many Ubuntu users. In this post, we will provide you with a simple alternative for making Gnome 3 or Classic Gnome desktop environment as your default login session.

Gnome 3 Auto Login
To make Gnome 3 as your auto login session, enter this command in Terminal:
sudo /usr/lib/lightdm/lightdm-set-defaults -s gnome-shell
Unity Auto login
In case you wish to make Unity the default session once more, use this command:
sudo /usr/lib/lightdm/lightdm-set-defaults -s ubuntu
Classic Gnome Auto login
To auto login to the Gnome classic desktop by default, use this command to install Gnome session fallback:
sudo apt-get install gnome-session-fallback
Once done, run this Terminal command:
sudo /usr/lib/lightdm/lightdm-set-defaults -s gnome-classic
It is likely that the GUI-based method of doing the above mentioned task may be resolved after a few Ubuntu 11.10 updates. However, it is also quite likely that you might end up inheriting more issues with the newer updates, due to the recent Canonical update blunders.
TKB:1035