Yep, in particular I recall a case involving AOL in which a man claimed negligence on the part of AOL for not policing their forums, allowing for people to defame him. The court ruled that providing that type of policing would have turned AOL into a publisher, which is exactly what 230 protects against.
Facebook claims users used their real names. That's pretty specific. If they are flagrantly ignoring a violation of their own claims, their legal standing seem different than an entity merely transmitting data.
I think the same thing would apply here.