The general idea is that as content circulates, it creates publics - not communities but the more rhetorically-focused publics.
Here: blog post On the problems of considering the differences between intended and unintended circulation. The issues considered here suggests the need for theorizing.
Main players: Trimbur (2000), Porter (2009), Ridolfo (2012)
Here: extract of article by Mary Stuckey, "On Rhetorical Circulation." Addresses concerns of appropriation in recirculation, increase in spreading of public discourse made possible by small bytes, recirculation and colonialism, and inter-relations between recirculation, invention, and judgment (kairos).
A related term is Rhetorical Velocity, from Sheridan, Ridolfo, and Michel.