As if to underscore its might in the rivalry with Apple that broke into a hot war this weekend, Amazon posted a 40% boost in net profits in 2009, $902 million on nearly $25 billion in sales.

Not all of it was books, but a significant contributor was Kindle, according to news agency AFP. Sales of the e-book reader helped produce a 71% profit in the last quarter of the year, making it the holiday gift of choice. CEO Jeff Bezos remains mum on actual sales of Kindle but stated that “Millions of people now own Kindles, and Kindle owners read, a lot. When we have both editions, we sell six Kindle books for every 10 physical books.” And that doesn’t include free books.

The press service added that “Forrester Research estimates the Kindle has a nearly 60 percent share of the US market followed by the Sony Reader with 35 percent and expects e-reader sales to double to six million units this year.”

We have a memo in our calendar to revisit these figures a year from now, when sales of Apple iPad and other rival devices are measured.

RC