Global sales of e-readers like Amazon.com's Kindle will reach 6.6 million devices by the end of 2010, and then jump 68 per cent to 11 million devices in 2011 as it battles popular media tablets such as Apple's iPad, Gartner said on Wednesday.

The dramatic growth projected for 2011 follows an 80 per cent jump from 2009 to 2010, Gartner noted. About 3.6 million e-readers were sold in 2009.

Amazon's Kindle are driving e-reader sales -- accounting for some 45 per cent to 50 per cent of all e-reader sales, according to anaysts from analyst firms, including Forrester Research and Yankee Group.

Yankee has predicted sales of million e-readers for 2010 , nearly matching Gartner's projection. Both firms define the e-reader market as separate from the market for media tablets like the iPad or Samsung's Galaxy Tablet.

North America will account for some 4 million e-reader sales in 2010, or nearly two-thirds of the worldwide total, Garner said. Hughes de la Vergne, an analyst at Gartner, said North America will remain a key e-reader market through 2014.

Amazon Kindle 3

E-readers generally tend to be lower cost and smaller than media tablets, and have a longer battery life. Most are still black and white, though Barnes & Noble introduced the color Nook e-reader this fall. Media tablets are the biggest threat to e-readers, Gartner said, primarily because they can be used for so many of the functions that are seen in many laptops.

Allen Weiner, another Gartner analyst, said e-reader makers will need to retain a price advantage to remain competitive. The third generation Kindle sells for $139, compared to an iPads starting price of $499.

Google this week announced Google eBook and eBookstore while Amazon.com announced an update for the Kindle for the Web application.

Both systems allow reading of books on a range of devices, not just e-readers, and invite readers to buy books from their separate e-book warehouses.