Aug. 11 (Bloomberg) -- Amazon.com Inc., the world's largest Internet retailer, may sell 380,000 of its Kindle electronic- reading devices in 2008, Citigroup analysts said, doubling their previous estimates.

``Kindle is becoming the iPod of the book world,'' Citigroup analyst Mark Mahaney wrote in a report dated yesterday. ``Kindle could be one of the top `gadget' gifts this holiday season.''

The retailer expanded digital sales, introducing Kindle last year to encourage book, magazine and newspaper downloads. Mahaney rates the stock ``buy.''

Amazon.com gained $5.33, or 6.6 percent, to $85.54 at 10:18 a.m. in Nasdaq Stock Market trading.

To contact the reporter on this story: Eric Martin in New York at emartin21@bloomberg.net.

Last Updated: August 11, 2008 10:27 EDT