Kindle's Killer App?

Could textbooks be Kindle's killer app? I sure would have loved not to have to lug around a giant pile of over-sized textbooks. To say nothing of the their outrageous prices and the bother of selling them at the end of the term. On the other hand, I'm not so sure I'd be able to get a handle on flipping to the place in the book where I needed to be. Another downside: black and white photos and graphs.