Photos: Amazon Kindle DX

The Kindle DX is the third iteration of Amazon's e-book reader. With the exception of its larger (9.7 inches) autorotating screen, native support for PDF files, and more expensive price tag ($489), its functionally is identical to the earlier Kindle 2.

The Kindle DX's 9.7-inch screen is considerably roomier than the Kindle 2's 6-inch version. That should mean less scrolling and fewer turned pages.

The e-ink display boasts a 1,200x824-pixel resolution (150 pixels per inch).

While it's considerably larger than the Kindle 2, the DX's 0.38-inch depth is just a hair larger than the small-screen model.

Earlier Kindles required Adobe PDFs to go through a conversion process first, but the Kindle DX is said to support the format natively.

While the backside of the Kindle DX is as nondescript as that of an iPod, it masks the unit's 4GB capacity (3.3GB usable). That's twice as much as the Kindle 2, and enough to hold 3,500 books (according to Amazon).

As with the Kindle 2, the DX's e-ink screen delivers 16 shades of gray, which means sharper images than the first-gen Kindle. (Those hoping for a color screen will have to wait for future versions.)

Newspapers, magazines, books, and personal documents are accessible on the Kindle DX. The unit also includes a full version of the New Oxford American Dictionary, so unfamiliar words can be looked up on the fly.

Unlike a paper magazines or newspapers, the Kindle DX lets you adjust the font size to your liking. It also offers a text-to-speech option that uses a synthetic voice to read aloud to you.

New to the Kindle series is screen rotation. Like the iPhone, the Kindle DX will automatically rotate the screen from portrait to landscape mode when you flip the unit on its side.

Unlike the competing Sony Reader, the latest Kindle still doesn't have a touch screen. However, the built-in keyboard makes it relatively easy to enter search terms and Web addresses.

The Kindle DX is set to debut in the summer of 2009 for a whopping $489.