Only people getting temp bans would be the chat nannies. I'd vote to ban them too out of general Interwebz principle, whether I agreed with them or not.
If "chat nannies" means what I think it means, they wouldn't have to be nannies with a player-initiated chat ban system anyway. They're only nannies because the terms of service are not sufficiently enforced.
If EA can't (or won't) do it, I say, Power to the People!