A quick tip for Chromium users who are using Ubuntu 12.04: the Chromium PPAs (Stable, Beta, Dev and Daily) haven't been updated since Chromium 18 but if you want to use the latest Chromium browser in Ubuntu, there are two new PPAs you can use, thanks to Alex Shkop.
The two Chromium PPAs are for Ubuntu 12.04 LTS Precise Pangolin only for now, one for the latest stable Chromium (version 21) and one for the development builds (version 23 at the time I'm writing this post).
Add the stable PPA and install Chromium in Ubuntu 12.04 using the following commands:
sudo add-apt-repository ppa:a-v-shkop/chromium
sudo apt-get update
sudo apt-get install chromium-browser
Or, if you want the latest dev builds in Ubuntu 12.04 Precise Pangolin, use the following commands:
sudo add-apt-repository ppa:a-v-shkop/chromium-dev sudo apt-get update sudo apt-get install chromium-browser