And more on What Youth Think website : http://www.whatyouththink.com/

The largest gain came from males ages 18 to 25, followed by women 26 to 34. Despite the already-large base of users under 35, those groups also posted the highest rates of growth. Increases in usage among older users, which was relatively stronger earlier in 2009, had slowed.

Younger women are nearly twice as likely as their Gen X counterparts to say they had discovered a new brand or product when a friend mentioned it in an online status update. They are also significantly more influenced by blogs, by both professionals and especially by “someone like me.”
What about the 'Cougar' Generation ? I'm sure they are as active as the Gen Y, in some other way.