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Amazon Kindle DX

Amazon reportedly sold out its first batch of the Kindle DX electronic-book reader in three days.

The online retailer started shipping the device late last week and ran out in 72 hours, according to media reports. Amazon is taking orders and plans to resume shipments June 17.

The Kindle DX is the second most popular electronic device on Amazon, behind the Kindle, which is the smaller version of the e-book reader. Amazon debuted the Kindle DX on May 6, which is when the retailer started taking pre-orders.

The Kindle DX has a 9.7-inch display versus the original Kindle's 6-inch screen. In addition, the larger device supports Adobe's popular PDF document file format and features the ability to switch from portrait to landscape mode by turning the device horizontally, both features that the smaller model lacks. The Kindle DX sells for $489 compared with $359 for the original.

Both Kindles use E Ink's display technology that shows crisper graphics and text without the eyestrain and glare associated with the backlight used in portable PCs. A unique feature in the devices is a wireless connection that lets users buy books and order magazine and newspaper subscriptions directly from Amazon. The connection is provided at no charge.

Amazon doesn't disclose the number of Kindles it has sold, but claims its accounts for 35% of book sales for those editions in which Kindle versions are available. Amazon's biggest rival in the e-book reader market is Sony, but Amazon could face stiff competition in the future from startup Plastic Logic, which is planning to start selling a device similar to the Kindle DX in the second half of the year.

Amazon also is facing competition from Web sites such as Scribd, which lets writers share documents with readers. The company last week started offering the electronic editions of thousands of Simon & Schuster novels, making them available for 20% less than the print editions.

Books from Scribd can be read on the site or through the Scribd-supplied reader for the PC. The company promises to launch a reader application for Apple's iPhone soon.

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