According to a Pew Internet & American Life study:
E-Reader ownership among U.S. adults age 18 and older doubled from 6% to 12% between November 2010 and May 2011, surging ahead of tablet adoption which stands at 8%, according to a new survey by the Pew Research Center’s Internet & American Life Project.
Over this six-month period, e-reader ownership grew at a faster pace among Hispanic adults than it did among white or African-American adults, and there was considerable growth in e-reader ownership among college graduates, one-fifth of whom (22%) now own this type of device. E-reader ownership is also rising faster among adults under age 50 than is the case among older adults.
Overall, the highest tablet ownership rates are among Hispanic adults (15%) and those with household incomes of at least $75,000 annually (17%). And for the first time, men are slightly more likely than women to own tablet computers.
(And, yes, I am aware that my headline can be parsed quite differently.)