U.S. Twitter usage surpasses earlier estimates

There will be 18 million U.S. adults who access Twitter on any platform at least monthly in 2009, a 200% increase over 2008 levels. Usage will reach 26 million U.S. adults next year, a further 44.4% climb. This forecast counts 11.1% of Internet users as Twitter users this year, a figure close in line with Harris Interactive and Pew Internet & American Life Project estimates of 13% and 11%, respectively, in spring 2009.