A few thoughts on How WordPress is Made:
Distributed work environments are going to become increasingly more common. Questions of how to foster team collaboration or create a company culture will become more complex.
Email is not very popular. Most of the work is done by P2s, IRC, and Skype. This one is a relief, since I was under the impression that I am the only one who dislikes email as a task tool.
They use P2 theme on WordPress as an internal collaboration tool. Matt’s blog post on How P2 Changed Automattic gives some more inside scoop. Definitely need to check this one out further.
And finally, they have a Happiness Team! And they like food!! I really should be working for WordPress. ;-)