The percentage of US adults who use an e-reader device such as a Kindle, iPad or Nook has almost doubled since 2010, according to Harris Poll results released in September 2011. Fifteen percent of adults say they use an e-reader, about 88% more than the 8% who used an e-reader in 2010.

Regionally, residents of the West are most likely to use an e-reader (20%, one-third more than the national average), closely followed by Easterners (19%). Conversely, only 9% of Midwesterners use an e-reader, 40% below the national average. With 14% e-reader usage, Southern adults are about 7% less likely than average to use an electronic reading device. In further good news for makers and promoters of e-readers, the percentage of adults who do not currently use an e-reader but plan to get one has risen 25%, from 12% to 15%, in the past year. There is no regional variation in this percentage, and most (11%) are somewhat likely, with only 4% very likely.

Another research also finds that the share of adults in the US who own an e-book reader doubled to 12% in May 2011 from 6% in November 2010, according to data from the Pew Research Center Internet & American Life Project. This is the first time since the Pew Internet Project began measuring e-reader use in April 2009 that ownership of this device has reached double digits among US adults.

Meanwhile, Pew data shows 8% of US adults owned a tablet computer in May 2011. This is roughly the same percentage of adults who reported owning this kind of device in January 2011 (7%), and represents 60% growth in ownership since November 2010. (Marketing Charts, September 2011)