26. The method of claim 20 , further comprising: receiving, at a second data-processing device, discussion content identified to be associated with the first discussion topic; and transmitting, by the second data-processing device, a notification to at least a discussion-topic server that new discussion content for the first discussion topic is available for transmission, wherein the notification identifies the first discussion topic.
27. The method of claim 26 , wherein the notification comprises an action metadata message that identifies at least one location from which the new discussion content may be retrieved.