I set up a twitter account for our association to notify members that are on twitter about important events involving the industry.
We have been trying to get the acronym for our association in all the social networking realms.
So far we have linkedin, facebook, ning, and twitter accounts. We have groups in facebook and linkedin.
Since associations are all about education and networking the social networking arena is an important place to be if you want to stay engaged with members.
Leveraging this new media is not complicated and allows you to get information out to a broader audience without using email.