There’s a really interesting article on Computer World about a wiki effectively being used as a textbook. As the professor says:

“My wiki is my textbook now,” he said. “This platform is infinitely better and gets better information from a variety of sources. It takes a year and half for a textbook to get published, and by the time that happens it is outdated. [The use of] textbooks will begin to fade … and these more collaborative-based, environment will probably rise to the surface.”
It’s quite an interesting idea – though I wonder what the publishers of $120 textbooks that are forced upon captive audiences think about it?