The Kindle Revolution.
I meant to link to this article earlier. It describes the impact devices like Kindle 2.0 and the Plastic Logic Reader will have on reading. The article does not address how these devices will completely overturn the academic textbook business, but that too is coming, and sooner than you think.
In the big picture, two very powerful forces (Google and Amazon) are amassing their armies to conquer every classroom around the world. They are digitizing every book and vertically integrating distribution. They will cut the cost of textbooks by more than half. And publishing companies that get in their way will be crushed.