Online retailer Amazon (Stock Quote: AMZN) announced yesterday that it is selling more e-books for its popular Kindle e-reader than hardcover books.

According to the company’s press release, Amazon has sold 143 Kindle books for every 100 hardcover books during the past three months. In the past month alone, has sold 180 Kindle books for every 100 hardcover books, a spike that might be directly correlated to the growing popularity of the Kindle itself. Sales for the device accelerated each month in the second quarter, an increase that Amazon attributes to the decrease in the Kindle’s price.

"We've reached a tipping point with the new price of Kindle” Jeff Bezos, founder and CEO of Amazon, said.  “The growth rate of Kindle device unit sales has tripled since we lowered the price from $259 to $189."

Amazon cut the price of the Kindle back in June just a few hours after Barnes & Noble (Stock Quote: BKS) slashed the price of its Nook e-reader from $259 to $199. Sony dropped the price of its three e-readers a few weeks later. All three retailers, it was believed, were responding to the competition from Apple’s multifunctional iPad.

Amazon did not say how many Kindle books they sold in comparison to paperback and hardcover books together. Most E-books are priced at $9.99 or less, which makes them cheaper than most hardcover releases, but more expensive than many paperbacks. However, Amazon did announce that they sold more e-books than actual books for the first time this past holiday season.

The growing popularity of e-books isn’t exactly surprising. Earlier this month, a usability study conducted by the Nielsen Norman Group said people are more satisfied when they read digital books versus a printed version.  And consumers point out that this satisfaction isn’t only because of the drop in price.
“I live in the British Virgin Islands where bookstores are scarce and postal service/shipping is unreliable,” Kindle owner Traci O'Dea tells MainStreet. “I went on Amazon to buy [Gerald Durrell's My Family and Other Animals] as a hard copy and thought that I wouldn't be getting it for at least three weeks, then I suddenly realized, ‘Oh, I can just put it on my Kindle,’ and I had it within two minutes.”

Bridget Forney, who also owns Amazon’s e-reader, adds, “I love my Kindle because I can read five books at once and not have to carry them all around with me in a bulky knapsack and consequently worry about the covers getting torn or the pages bent.”

Does anyone still think e-readers are a fad? Let us know in the comments section below.

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