In reporting, Jeff Bezos finally mentioned something involving numbers with respect to Kindles, which are now owned by “millions of people.” And ratio of Kindle sales to print sales continues to grow: “when we have both editions, we sell 6 Kindle books for every 10 physical books.” Bezos even indicated specifically, “this is year-to-date and includes only paid books — free Kindle books would make the number even higher.” Amazon reported a huge fourth quarter, with sales of $9.52 billion, 42 percent higher than a year ago. Net income rose even more, up 71 percent at $384 million. North American […]