Instant Messaging--Another Format to Worry About?
http://www.stc.org/intercom/PDFs/2003/200301_36-37.pdf

Perlin, Neil E.
Intercom
2003

Abstract:

IM lived for years as an obscure technology in the shadow of the WAP (wireless application protocol) wireless Web, and is still used chiefly by teenagers. But IM has recently become a source of revenue for financially beleaguered telecoms, and has been discussed as a possible replacement for e-mail.