Scott McLemee has written an amusing essay about the transition of a 45 year old to using chat and IM; it is published as "Cogito Interruptus" in Inside Higher Education today and available at http://www.insidehighered.com/views/2008/08/20/mclemee.

Here is the concluding part of his essay:

"At one level, texting and IM are just slight variations on the now-familiar medium of e-mail. They tend to be even more casual — without so much formality as a subject line, even — yet they finally seem more similar to e-mail than anything else.

But now that e-mail itself is both so commonplace and so prone to abuse (“naked Angelina Jolie pics here!”), these supplementary forms have a slightly different valence. They seem more urgent. In the case of IM in particular, there is a suggestion of presence – the sense of an individual on the other end, waiting for a reply. (Indeed, the IM format indicates whether someone you know is online at a given time. The window indicates when a person is typing something to send to you.)

For anyone now accustomed to texting and IM – that is, most people in their teens and 20s – all of this goes without saying. And for lots of folks over a certain age, it probably won’t matter: the number of people in their social circles using these format won’t reach critical mass.

Those of us stuck in between, though, are left with questions about civility. Do you have to respond? How rude is it not to do so? (The other day, I ignored an IM from a friend and still feel positively antisocial for it.) Is it necessary to withdraw entirely from all forms of digital communication for a while, just to sustain, as Baudrillard put it two decades ago, “the minimal separation of public and private ... a restricted space”? And will withdrawal even be a possible, a few years down the line?"