People of all ages play games. I used to play counter-strike with some guys that were in their 40's and 50's several years ago (and several of them were good pubbers, what they lacked in reflexes they made up for with savvy). I expect that the teens and young adults will make up the majority of the poll though, as they were the generation that grew up with games as a source of entertainment (I can still fondly remember playing the 2600 my parents had, which should easily indicate for the more knowledgeable posters approximately what my age is).
Although, this would have been better served to have been posted on the general discussion forums, as the new player forum is only for people new to the game to ask questions about game mechanics and such (and is thus not often visited by most of the forumites).