How to install latest GIMP on Ubuntu

The GIMP that ships with Ubuntu can get quite old over the lifetime of the OS. Thankfully, Otto Kesselgulasch maintains a PPA from which the latest version of GIMP can be installed easily:

$ sudo add-apt-repository ppa:otto-kesselgulasch/gimp
$ sudo apt-get update
$ sudo apt-get install gimp

Tried with: GIMP 2.8 and Ubuntu 12.04