You're welcome! I haven't decided how I'm going to share source code. For my current series, I'm committing after every episode and posting on GitHub [1], so I'll do at least that much. Your idea of committing after every step of the TDD cycle is a really interesting one, but I'm not sure if could do that without it detracting from the videos. I've added it to my list of neat ideas.
[1] https://github.com/jamesshore/lets_play_tdd/commits/master