Exactly as predicted by critics, Amazon has begun flexing its muscle as the dominant e-book seller, and is now trying to renegotiate better deals with publishers to help its sagging bottom line. It is currently engaged in a very public fight with Hatchette, and has removed a number of best-sellers from its store as well as delayed or refused orders for other (physical) books. As with Walmart and some other outlets, Apple’s iBookstore is now offering discounted pre-orders on the “missing from Amazon” books….