New Biology Textbooks....Virtually

"Principles of Biology," a new textbook will be available for college students through technology only. This new book from Nature Publishing Group will sell this book for $49, providing unlimited internet access to information, interactive illustrations, and learning modules. While most science textbooks available online are still shown in pdf form, this text "book" is more of an interactive and virtual learning experience. With the rise in popularity of tablets and laptops, is this the direction all of our text books are going towards?

http://www.nytimes.com/2011/12/18/business/online-textbooks-aim-to-make-science-leap-from-the-page.html?_r=1&ref=science