That I don't know. :-( My main idea was that you can "circumvent" the maximum of 50 groups, if you participate (without joining) an "open" group.
Both the Carolina Chapter (@stc_carolina) and the Technical Editing SIG (@stc_te_sig) have included Twitter in their overall communication plans. Some things we tweet: - Jobs - Announcements & community news - Calendar events And the *great* thing is that all of these items are tweeted *automagically* -- no user involvement. We also "live tweet" during meetings and events. The TE SIG created a "formal" Twitter policy: http://www.stc-techedit.org/Twitter+Policy