Nielsen has produced a report on teens and the internet in an attempt to throw light on some of the myths which surround internet usage. You can download a free copy of the report here. It has provided some interesting insights namely

Teens are NOT abandoning TV for new media: In fact, they watch more TV than ever, up 6% over the past five years in the U.S.
Teens love the Internet … but spend far less time browsing than adults: Teens spend 11 hours and 32 minutes per month online. Far below the average of 29 hours and 15 minutes.
Teens watch …read more

Nielsen has produced the Three Screen Report for the 1st Quarter of 2009. The report shows that
“the average American every month watches approximately 153 hours of TV at home. In addition, the 131 million Americans who watch video on the Internet watch on average about 3 hours of video online each month at home or work. The 13.4 million Americans who watch video on mobile phones watch on average about 3 ½ hours of mobile video each month.”
It does show a general trend that teenagers are watching more and more video on their mobile, 18-24 timeshift their viewing and the …read more