Amazon has announced its third Kindle product, the Kindle DX. Designed to handle larger, more complex documents than the company’s recently released Kindle 2, which has been compared with the smaller iPhone, the Kindle DX features a 9.7-inch, 1200 x 824 E-Ink electronic paper display that can display newspaper and magazine pages at closer to full size. Kindle DX adds automatic screen rotation to landscape orientation, a built-in PDF reader—prior Kindle models could only read PDF-formatted documents after they had been converted into a Kindle-friendly format—4GB of internal storage, and a battery that supports four days of use with wireless on, or 20 days of use with wireless off. Like the Kindle 2, it also sports built-in EVDO Whispernet wireless downloading that is included for free for the life of the device, stereo speakers, a 3.5mm audio jack, a built-in dictionary, and more. Amazon’s Kindle DX is available for pre-order now for $489 and will be released this summer.