this should speak for itself, really. I would submit to you that if there is a correlation between high-risk behaviour and texting/social networking, it would seem likely that those individuals more prone to addiction (eg., drugs, alcohol) would of course become addicted to text messaging and facebook. I can't say with any certainty that these stimuli push the same buttons in the brain, but that's my hypothesis for the moment
As an aside, I take issue with the idea that teens reporting "no texting" activity is 'on the bright side', as the article puts it. Really, Ars? You're really playing the grumpy old dude who can't understand young people these days, and in my day we didn't text message by golly if we wanted to see someone we walked to their house? Argh!