I just ran across this article on CNN.com about a new poll by AP-AOL on generational IM habits. The poll found that there is a pretty wide gap in IM usage between teens and "adults". Interesting stats: 48% of 13-18 year olds use IM (this is more than 2x the number of "adults" - I honestly thought the number of IMing teens would be higher!),more than half the IMing teens send at least 25 messages per day, and 16% of teens have used IM to break up with someone (I got dumped over the phone many a time, so is IM break-up really so different?).
The article does point out that there are exceptions to the generational differences though, as we found out here when starting our IM reference service. We had several librarians of the general Boomer generation who fell in love with IM and some younger librarians who aren't remotely interested. And I did have a friend tell me last week that her 10 yr old daughter just showed her how to IM (although I have yet to see any successful IMing from her!). I think that trend of parents learning about technology from their children will continue and maybe reduce the "IM gap".
The (probably not so newsy)lesson here? Lots of teens and youngers IM. Let folks IM on your library computers. And set up IM for reference and other interaction. It's free and easy and more and mroe folks are going to expect it.