On May 19, Amazon reported its e-books sales surpassed its combined hardcover and paperback book sales. “We never imagined it would happen that quickly,” CEO Jeff Bezos said in a statement. Citi Investment Research analyst Mark Mahaney estimates Amazon will sell 17.5 million Kindles this year and 310 million e-books, for a combined $3.8 billion. Jane Friedman, co-founder and CEO of Open Road, a digital book publisher whose authors include the late William Styron, can attest to the device’s power. In June, Open Road allowed Styron’s Sophie’s Choice to be sold at a discount for the Kindle as part of an Amazon promotion. “Not only did Sophie’s Choice get a sales bump,” she says, “the other Styron titles also got a bump. That’s when you know something is really working.”

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