1. A computer-implemented method, comprising: identifying a plurality of users participating in a multi-user communication, wherein each user participates using a communication device that communicates with the communication devices of other users over a network; determining a topic of the multi-user communication between the communication devices of the plurality of users; obtaining a topical expertise level relative to the topic for each of the identified users; ranking each user participating in the multi-user communication according to the topical expertise level for each user; and assigning the user with the highest topical expertise rank as the moderator, wherein the communication device of the moderator is provided an ability selected from an ability to mute input from the communication device of any of the other users and an ability to delete a post from the communication device of any of the other users.
9. The method of claim 1 , wherein obtaining a topical expertise level relative to the topic for each of the users participating in the multi-user communication, includes obtaining endorsements from others regarding a topical expertise level of each user relative to the topic.