I like the wiki idea for a textbook. I think that works in a lot of ways. That does lead in to my next question, which is what exactly the chapter threads would be? Would they be lectures? (If so, how would they different than the textbook chapters? Spoken lectures aren't easily done here.) Would they be "office hours," the posting and answering of questions? Either way, they should include links to online animations and demos where possible. These would be things that exist on the web, but shouldn't be included in the wiki for whatever reason. Those are my thoughts on the topic.

(That book also has *a lot* of holes and articles that are severely lacking.)