Across the United States you will find a wave of students now using e-readers and tablets instead of using text books. Digital Reading has swept across college campuses faster than you can say English literature 101. The main reason for this is the increased cost of text books, with prices going up every year. So obviously it's with text books that the real revolution is building with digital versions already costing just a fraction of the hard copies.
Analysts see it moving quickly too, it may take a couple of years but don't be surprised if the text book market really shifted online in a huge way over the course of 3 to 4 years. Even including the price of e-readers, expenses can be slashed considerably, a fact that online retailer giant Amazon.com recognizes and has already has a section dedicated to text books for e-readers. The ability to access the data from any computer, tablet, or smartphone you have is huge.
There is also an upside for publishers by way of reducing overheard costs, you're not selling the physical books in stores but in the long term you're getting rid of those hard costs of printing and transporting those text books. Digital text books are only about 1% of the text book market now but that's expected to grow by 20% by 2015.