3. The method of claim 2 , further comprising measuring the performance of the advertising campaign using the advertising targeting server system.
4. The method of claim 3 , wherein measuring the performance of the advertising campaign further comprises: obtaining a set of messages related to the advertising campaign within the online social network using the advertising targeting server system, where the messages were posted by members of the online social network; and determining if the members that posted the messages in the set of messages are associated with the member groups targeted by the advertising campaign using the advertising targeting server system.