If IM, Skype, and text are verbs in your vocabulary, you won't need this information. However, if teenagers and techies seem to be speaking a language you don't understand, here's a communications tutorial from the New York Times that will help. Written from the point of view of a college student explaining it all to his parents, the article makes text messaging, instant messaging, video chatting, and internet phone calls easy to understand. (It even addresses Mac/PC compatibilities.) When you're ready to try it, here's another site with about 250 text messaging abbreviations that will come in handy.
Even if you decide to stick with "old-fashioned" cell phones and email, at least you'll know what your kids are talking about. IYKWIM.