Amazon (Stock Quote: AMZN) announced Wednesday that it will sell a third type of its popular Kindle e-reader that will rely solely on Wi-Fi for Internet access. The new Kindle Wi-Fi, available for pre-order now on the website, comes at the relatively low cost of $139.

The online retailer also unveiled an updated version of its $189 e-reader, the Kindle 3G with Wi-Fi and its $379 Kindle DX. The latest generation of Kindle, which includes the 3G and Wi-Fi devices, is smaller and lighter, though the six-inch reading area remains the same. The Kindle 3G has “go anywhere” wireless capabilities that don’t require monthly payments or the purchase of a data plan, unlike the cheaper Kindle Wi-Fi , which can only be used in locations that have access to a Wi-Fi hotspot. A single battery charge will now keep all three Kindles powered for up to a month and they can all now carry up to 3,500 books.

More notably, however, is that the new Kindles have a unique high-contrast e-Ink screen, which, according to Amazon, offers “50% better contrast than any other e-Reader” and absolutely no sun glare. This selling point is no doubt intended to distinguish the Kindle from its main competitor, Apple’s multifunctional, albeit $499-$829 iPad.   

Both the updated Kindle 3G and the new Kindle Wi-Fi will be shipped Aug. 27.  

These new releases are only part of Amazon’s recent efforts in achieving e-reader world domination. In June, Amazon slashed its second-generation Kindle’s price from $259 to $189. The decrease came a day after Barnes and Noble lowered the price of its Nook to $199. The move ultimately led to a subsequent spike in Kindle sales … and the e-books that are available for it. Amazon announced recently that it is selling more e-books than actual hardcover copies in its online store. The second-generation Kindle, additionally, sold out on July 28.

Amazon, for its part, seems to want consumers to believe that its Kindle craze hasn’t been in response to the iPad’s popularity.
“I believe in the power of transformative reading, the ability of an author to transport you to new worlds, introduce you to new people and even alter your perspective,” Amazon CEO Jeff Bezos said in a letter to customers. “Reading is important. Reading is why we build Kindles. Reading is why millions of people use Kindles.”

Whatever the reason, customers are, well, buying it. Massachusetts consultant and Kindle owner Lillian Arleque calls her e-reader “the best thing that ever happened to literacy.”

Check out this MainStreet article on a study that shows more people are satisfied with their e-reader than a printed book.

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