Nook? QUE? Alex? Sony Reader? Kindle? E-reader Business Heats Up

It follows recent introductions of similar devices, including the Plastic Logic QUE, the Spring Design Alex, the Sony Reader, and the Amazon Kindle.

Barnes & Noble on Wednesday finally unveiled its Nook e-reader, a dual-screen device based on Google Android technology and an E-Ink display which allows the downloading, reading, and sharing of free and paid-for e-books.

The Nook, which is expected to be available late next month with a retail price of $259, enters what is becoming a very crowded e-reader device market.

Just this past Monday, for instance, two other newcomers to the e-reader market unveiled their devices.

One of those was Plastic Logic, which introduced its QUE proReader e-reader. Plastic Logic is targeting the QUE at business users by making media deals with news and financial information providers and providing the ability to work with Microsoft's Word, PowerPoint, and Excel applications.

The other was Spring Design, which introduced its Alex e-reader. The Alex, like the Nook, is based on Google Android technology. Spring Design said it is targeting professional, educational, and entertainment markets.

Sony has recently introduced a new generation of its Reader series of e-readers.

Sony is also starting to show its upcoming Reader Daily Edition, which has a 7-inch touch display and includes free 3G broadband access for browsing Sony-specified sites for on-the-go content, as well as USB connectivity for downloading other reading materials. The Sony device is slated to be released in December.

The Amazon Kindle, which sparked the recent interest in e-readers, remains the device against which the others are measured.