In a recent survey by ExactTarget, U.S. teens (ages 15-17) say they prefer texting over other methods of communication including email and Facebook.

Texting was the communication activity teens were most likely to report having increased over the past six months, according to the ExactTarget survey. There were also significant numbers of teens using Facebook, meeting in person and communicating via e-mail more, but most respondents held those activities steady.

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Source: eMarketer
http://www.emarketer.com/Article.aspx?R=1007737