Is it the communication or the device that creates the addiction? Keith Hampton of U.Penn's Annenberg School of Communication was quoted in an ABC News article about the Blackberry blackout in April. He's got the primary stuff on his blog: CrackBerry : I think not:
‘You can’t be addicted to communication,’ Hampton said. ‘We’re all social animals. We want to communicate with those around us. And the BlackBerry is just one of many types of communication that help facilitate that.’
[found via Howard Rheingold on Smart Mobs]
This is an interesting aspect to this discussion. But my comment is that the addiction isn't the communication. The addiction is the tool, whether it's a CrackBerry or the little "new mail" bubble that Outlook throws at you or the jingle of your phone. If you can't ignore the tool and keep working on your important projects, then there are elements of addiction. If you can't go ten minutes without checking for new messages; if your tools drive your life, there are element of addiction.