Using Wiki in Education

Has anyone read this book? (http://www.wikiineducation.com/display/ikiw/Home) I'm trying to decide if it's worth the money. I did see that Vicki Davis wrote a chapter.

There's something about a Creative Commons licensed book that is $19 that I don't quite get. (Could I then share the book with others for free? That's what the license says.) But the content looks interesting.