According to several reports, Amazon is now lowering its book discounts.
While Amazon isn't exactly a bookstore anymore, it did come to dominate the market by offering lower prices and undercutting the competition. This isn't great if you shop for books a lot, but it might be just was the doctor ordered if you are a shareholder.
I've written a good bit about just how insane Amazon's valuation is (here, and here) but I think that this move might be a good one. The ultra-bull theory for Amazon is that it will be able to "flip the switch" and start generating profits after years of expanding and funneling all revenues back into growing the business. The market seems to be pretty happy with this strategy, at least happy enough to give Amazon a PE ratio north of 200.