Today, both the FTC and the State of California weighed in regarding the case against Facebook over "Sponsored Stories." (As we've discussed, several objectors are challenging the class settlement in this case because it authorizes Facebook to use minors' images for advertising in violation of seven states' privacy laws.) Although neither the FTC nor California took a position on the case as a whole, both briefs provided support to the challengers by rebutting one of Facebook's key arguments: that state law privacy protections should be disregarded because they are preempted by federal law.
Here's a New York Times story about the briefs.
(Disclosure: five of the objectors are represented by Public Citizen.)