Do Open Source Text Books Work?

I just found an article by Ben Crowell titled: " Do Open-Source Books Work?" from http://www.lightandmatter.com/article/article.html

He raises a number of interesting points about open source text books. He focuses on the intention and the licensing of the books. Starting with Benjamin Franklin and his use of the lending library to "free" information and release it to the masses. With us in the information revolution, are we taking this concept seriously? He suggests we seem to be going in the opposite direction when it comes to texts for school and university study.

He discussed the Biophysics Textbook On-Line (BTOL) which is "collaborative but closed-source". One of the authors commented on the success of BTOL: "The BTOL is tied to a Society that already has an established community, regular meetings, newsletters, etc. We tap into all of this structure. For example, when a new article is posted we announce it in the Biophysical Society Newsletter. I would think that other fields might benefit from endorsement by an established society that already serves the field."

I am building a picture of Open Source Text Books that is different to my original intention, and now I think it is time to clarify this intention.