Are free, online textbooks the answer?

The Los Angeles Times has a nice article about one way professors are helping their students to afford college. R. Preston McAffee (an economics professor at Caltech) has written a free, open-source textbook and made it available online. This book is so highly regarded that it has been adopted by many prestigious universities, including Harvard. Is this a possible answer to the rising costs of textbooks?

Congress recently passed laws that would require textbook publishers to offer "un-bundled" editions of books, so students won't be forced into buying workbooks and DVDs that aren't used in classes. While this is a good first step, people like R. Preston McAffee believe that this doesn't go nearly far enough to help students cope. You can read the complete article here.