Amazon has released a new version of its Kindle e-book reader featuring, as expected, a larger screen designed to accommodate newspaper and magazine content.

The Amazon Kindle DX includes a 9.7in display - an upgrade from the 6in screen on the Kindle 2, which launched in the US in February.

"The reason we still print so much is that traditional computer displays are a worse display device than paper," said Amazon boss Jeff Bezos. "Kindle's paper-like display solves that problem. But most of the documents we print and read are 8.5-by-11in. The information on those documents is structured to be read [in that form]."

A note on Amazon's US website says the Kindle DX's screen is large enough so you can read PDF files natively without scrolling, panning or zooming.

It's also more expensive than the Kindle 2: the Kindle DX will cost $489 in the US compared with $359 for the earlier model.

Amazon is taking pre-orders now, but has yet to reveal a release date.

However, The New York Times Company and Washington Post Company have announced that they are planning pilots with the Kindle DX this summer. The newpapers will offer the Kindle DX at a reduced price to readers who live in areas in the US where home-delivery is not available and who sign up for a long-term subscription to the Kindle edition of the newspapers, the company said.