In a stealthy yet significant move, Amazon has dropped Sprint as its wireless partner for the latest versions of the Kindle 2 e-book reader. From now on, new Kindle 2s, in the U.S. and worldwide, will be powered exclusively by AT&T’s 3G network.

“Due to strong customer demand for the new Kindle with U.S. and international wireless , we are consolidating our family of 6-inch Kindles,” says Drew Herdener, spokesperson for Amazon.

The move was announced in a quiet update to Amazon’s product page for the Kindle rather than through a press announcement.

The move is a big blow to Sprint, which was the first U.S. telecom carrier to experiment with supporting mobile devices beyond cellphones and netbooks. It also means AT&T has all but cornered the wireless -connectivity market for e-readers. In addition to the Kindle 2, AT&T’s network forms the backbone of the new Sony touchscreen reader and Barnes & Noble’s recently introduced Nook e-reader. All that’s left for Sprint? Providing service for Amazon’s XL-sized Kindle DX, and supporting all the existing Sprint-connected Kindles.

When Amazon introduced the Kindle in 2007, the company highlighted wireless downloads of books as the device’s unique feature. The move helped the Kindle gain an edge over Sony, which had introduced its e-reader earlier but without wireless connectivity.

Earlier this year, Amazon offered a second-generation Kindle called Kindle 2 and a big-screen reader called the Kindle DX. Kindle 2 has a basic browser and lets users check text-heavy sites such as Wikipedia. But the devices were restricted to the United States.

Finally, this month, Amazon debuted an international version of the Kindle 2. It was the first Kindle to use AT&T’s network instead of Sprint’s. Kindle DX is still not available outside the states.

“Now that they are selling a Kindle overseas, it makes sense for them to have just one product that they can sell in all markets,” says Charles Golvin, an analyst with Forrester Research. “And, since, in most of the world GSM is what is used, having a single product helps drive down costs for Amazon.” Sprint’s network is based on the CDMA standard.

That doesn’t mean Kindle buyers who bought their device before October will be switching to AT&T.

“Existing Kindle users, owners of the first- and second-generation Kindles and Kindle DX, will not notice any change to their experience. They will continue to utilize the Sprint network in the U.S.,” says Herdener.

And at least until Amazon introduces an international version of Kindle DX, Sprint will continue to be in business with Amazon.

“Sprint still powers the Kindle DX,” a Sprint spokesperson told Wired.com. “So it is not accurate to say that our relationship with Amazon is over.”

Meanwhile, for Kindle users, the switch from Sprint to AT&T raises questions about reliability of service. Weighed down by heavy data use from the iPhone , AT&T’s U.S. network has become congested, leading to slow connectivity and dropped calls.

And with about 3 million e-readers expected to be sold next year, could AT&T’s network face additional strain? Not really, says Golvin. “The type of connection that the Kindle needs is different from that of a phone, since there is no voice component, only a data component,” he says. “The actual capacity consumed by all Kindles now and those coming on to the network is very, very small compared to the rest of the network.”

Kindle users are also less likely to notice small delays or disturbances in the network, says Forrester’s Golvin. Unlike a web page, downloading a book does not require near–real-time display of different components.

“On an e-book reader, the congestion is invisible,” says Golvin. “The downloaded book arrives when it arrives, and a few seconds’ wait does not change much.”

See Also:

Hands-on with International KindleBarnes & Noble Unveils Kindle-Killing, Dual-Screen ‘Nook’ E-ReaderAmazon Kills U.S. Kindle, Cuts International PriceInternational Kindle Now Shipping: The Good, the Bad and the Ugly
Kindle Goes International — With a Little Help From AT&TReview: Amazon.com Kindle 2
Review: Amazon.com Kindle DX

Top photo: Jim Merithew/Wired.com
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