Nautilus was the flagship product of the now-defunct Eazel Inc. Released under the terms of the GNU Lesser General Public License, Nautilus is free software.
What is new in 3.6
Version 3.6 introduced a revamp UX design, symbolic sidebar icon, new search feature, removal of many features such as setting window background, emblems, split pane mode, spatial mode. Nautilus application name was renamed to Files.With such major changes brought many criticisms from various vendors such as Linux Mint decided to fork version 3.2
Install nautilus 3.6 in ubuntu 12.10
Open the terminal and run the following comamnds
sudo add-apt-repository ppa:gnome3-team/gnome3
sudo apt-get update
sudo apt-get install nautilus