The github_post_receive.php script provides a function which will decode the
post-receive JSON object which github sends whenever a push occurs.  An
example of how to use it is provided in example_post_receive.php.  You can
ask github to send you the JSON whenever someone pushes into the repository
by going to the github Admin page, then the Service Hooks tab, and a URL to
the Post-Receive URLs list.

In addition, a very simple script list.php provides an interface to let
users sign up to receive emails from you (in particular, the post-receive
emails).  If you decide to use this, use list_create.php to create your
list and then remove that file.  In the future, it would be nice to email
a project's watchers when a change occurs, but there is no support in the
github API to get their usernames at the moment.

Subscribe to this project's post-receive updates at:
http://yuba.stanford.edu/github/list.php?list=github-post-receive-php-handler&co=1