You may want to have a look at the git mailing list. Instead of using something like githubs pull requests, all changes are exchanged through the mailinglist. As a result, you have really expressive commit messages. I am a big fan of that development model as you can read the whole discussion about a single line change within the commit message.

http://news.gmane.org/gmane.comp.version-control.git

edit: with "git send-email master..origin" all your commits will be send as seperated emails to someone you choose. Afterwards, the receiver can easily get the commits from his mbox via "git am".

There is a git command called git-format-patch that lets you format patches for email. This script then _encodes_ this into a PNG and you can tweet it.

I've added more detail to the README on what happens (refresh, it is probably cached. GitHub pages does that). My implementation of the idea just a couple of scripts and is far from ideal (has dependencies, need twitter api key), but I hope someone likes the concept and builds on the idea.