The folks at the Pew Research Center have come out with a new report showing that the number of U.S. adults who own tablets and e-book readers each jumped from 10 percent to 19 percent between mid-December and early January.

Overall, 29 percent of adults now own at least one of them, up from 18 percent in Decemberaccording to Pew, which notes that "these findings are striking because they come after a period from mid-2011 into the autumn in which there was not much change in the ownership of tablets and e-book readers."

The report, from the Pew Internet and American Life Project, attributed some of that change to the arrival of Amazon's Kindle Fire and Barnes & Noble's Nook Tablet, both of which cost less than other tablets on the market.

Microsoft is late coming into the tablet market. Its Windows 8 -- the latest version of its flagship operating system that's designed to work on both tablets and desktop computers -- comes out in beta next month.