in an analyst Q&A session during E3 in Los Angeles last week, Fils-Aime cited a February survey from independent market research firm Ipsos that found 51 percent of adult (18+) Wii owners use the console at least one to two hours a week.
http://www.gamasutra.com/view/news/29081/Nintendo_Adults_More_Active_On_Wii_Than_Xbox_360_PS3.php