Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
GNOME Shell is GNOME foundation's official shell for GNOME 3.0 and as we have seen in so many posts before, GNOME Shell is an incredibly good alternative for Canonical's Unity UI which became the default Ubuntu interface starting from Natty Narwhal release. The least you can say is, now you have two unique interfaces to choose from instead of plain vanilla GNOME. Top things to do after installing GNOME Shell in Ubuntu 11.10.
Install GNOME Tweak Tool
GNOME Tweak Tool should have been a default application. One of the most important complaint about GNOME Shell is that, it hides a lot more than it should be doing.