This script runs over the entire of the Android repo checkout, classifying the contents in terms of contents and creating a bunch of stats.
Why? If you base a large amount of revenue around a huge piece of SW that keeps getting updated under your feet, it pays to understand what is changing at a meta level as well as being able to classying a patch or full release from Google super quick to estimate when a port might be complete.
The public side of this is written up here:
http://the-mighty-fidget.blogspot.com/2013/04/measuring-success-charting-android-open.html