Bookseller Barnes & Noble is holding a "major event" in New York City this afternoon where it's expected to unveil its own dedicated electronic reader to compete with the likes of Amazon's Kindle. Details have been leaking out ahead of the official announcement. The device is called "Nook," according to reports, and will sell for $259, the same price as the basic Kindle.

Photos of the device popped up earlier on Gizmodo, showing an interesting Kindle-iPhone hybrid, with black-and-white e-ink screen on top and color touch display on the bottom.

Update: It's official. The Nook is priced at $259. Looks pretty slick. More product images and details below.

Forrester Research analyst Sarah Rotman Epps expressed surprise that Barnes & Noble is pricing the Nook at $259.

"This puts the Nook competing squarely with Amazon's Kindle 2 — most likely with a razor thin margin, if any, for B&N," Epps wrote in a blog post. "To steal market share from Amazon and make up for lost time, B&N is pricing the Nook as aggressively as possible."

Epps said Barnes & Noble has some assets to help it market Nook, including 700 physical retail stores in 50 states, but added that "B&N will need to use all the tools in its arsenal" to gain ground on Amazon, which launched its first Kindle in 2007.

Barnes & Noble launched an electronic book store in July that includes hundreds of thousands of free public domain books scanned by search giant Google. The bookseller also has deals to supply its e-books to forthcoming readers from Plastic Logic and Irex.

I'll be following the announcement and will update with details as they become available.

Update: As expected, the Nook has a black-and-white E Ink display for reading on top and a color LCD touch screen for navigation on the bottom. The top screen is 6" and the bottom screen is 3.5". The device lets users wirelessly download books and other content via AT&T or Wi-Fi.

The Nook has 2GB of memory (up to 1,500 books) and a slot for adding up to 16GB more. It runs on the Google Android operating system and supports the ePub open format for electronic books. It also has a feature for lending digital books, and a built-in MP3 player.

Barnes & Noble says the Nook is the same size and weight as a paperback book. It starts shipping in November.

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