David Teather in The Guardian says :
Amazon claims to have sold 143 digital books for its e-reader, the Kindle, for every 100 hardback books over the past three months. The pace of change is also accelerating. Amazon said that in the most recent four weeks, the rate reached 180 ebooks for every 100 hardbacks sold. Jeff Bezos, founder of Amazon, said sales of the Kindle and ebooks had reached a "tipping point", with five authors including Steig Larsson, the writer of Girl with a Dragon Tattoo, and Stephenie Meyer, who penned the Twilight series, each selling more than 500,000 digital books. Earlier this month, Hachette said that James Patterson had sold 1.1m ebooks to date.But there's good news for lovers of the physical book, he says, apparently sales of hardbacks are up 22% this year in the US.
Elsewhere, David Carnon looks at what Amazon aren't telling us about the surge in e-book buying, and Larry Dignan reckons it is the introduction of the i-Pad (and not the Kindle) that is driving sales.