The non-profit Pew Internet & American Life project regularly cranks out incredibly valuable market research. Their latest study on Teens and Social Media is no exception. It compares use of different kinds of social media between boys and girls, and the different media channels they use.
To give you an idea of the quality of the data in the report, here's one table that caught my eye.
That there's a pronounced shift in media usage underway in the next generation shouldn't be any revelation. However, the fact that the telephone is still such an important part of their lives was quite surprising to me. My view has been that teens are primarily text and IM communicators.