The Talmud and the Open Source movement are similar in an interesting way. Any rabbi can add on to the Talmud, but he or she must enter into training and earn a certain level of reputation. Then their writings are listed alongside centuries of others around the original text, which is then read and pondered by faithful members of the covenant.
Likewise, the source code is open to anyone, but it takes experts to look for bugs and clean up. While I can consume their software, I do not have the expertise to enter the source code; it takes training, much like the rabbis with the Talmud, to enter that conversation.
I recommend reading this short novel to anyone who is interested in the ties that bind or in the idea of an "open" book or source.