1. A method of providing marketing advocacy over a network, the method comprising: accessing a datastore to obtain one or more attributes of a network user, one or more attributes of an object of interest to the user, and one or more attributes of one or more advocates of consumption of the object; determining, for each of the one or more advocates of consumption in the object, a measure of the value of the relationship between the advocate and the object, denoted knowledge, and a measure of the value of the relationship between the advocate and the network user, denoted connection; combining the knowledge and connection measures to estimate a net value of marketing advocacy for each of the advocates of consumption of the object; sorting the advocates using the estimated net value of marketing advocacy; and facilitating communication between the network user and one or more advocates with largest net marketing value.