The main NCI group IM channel is intended for live help for new users, in as effective and targeted a way as the communications system permits. While a certain amount of latitude is given (because we were all new users once, and sometimes new users don't know any better) we try to take a relatively relaxed stance towards a number of activities.
However, we do not permit:
Recruiting
Begging/Panhandling
Proselytizing, preaching, promotion of products, services, groups or businesses (Yes, this a bit of a tough call to nail down exactly what is and what isn't, but we'd rather err on the side of caution)
Spam
Non-PG speech (Defined by Linden Lab as unsuitable “for grade-schoolers or grandma”)
Hate speech, insults, defamatory speech (or any other form of speech that is forbidden by the Second Life Community Standards or Terms of Service)
Disruption or rules-lawyering (in our sole determination)
Anything else that we believe prevents or diminishes the effective use of the group for announcements and assisting new users, because frankly the world is a complex place and no simple set of rules can really cover everything to everyone's satisfaction.