This should read is Trolling dead? Facebook has been known to protect privacy but you must use your real name. Their recent changes with privacy settings would mean that protections are loosing designed and easily changed.
Social media hasn't changed privacy or anonymous trolling behavior. Many people put their personal information out in the social web and trolls continue to troll no matter how the environments are designed. I have been involved in tech/internet and as a result trolls since the days of BBS boards and AOL. I don't think anything has changed, trolling will never be dead. Those that have mean things to say will say them anon or not.
Formspring has created another space for anonymous questions however my answer isn't anonymous. If I am engaging with someone in the social web I would like to know who I am talking to whether we agree, disagree or if they just want to say something mean. The point of social in social technology is interaction good, bad or other why would it be different than my #RL.