Probably nothing.
On the other hand, come to think of it, despite OWS being broken up by fancy new approaches ( rumor has it, Walls Street got spooked enough to see what effective methods can be employed given that Pinkerton approach would have been frowned upon then ), I don't recall FBI marking the participants in any special way ( please correct me if I am missting anything ).
I think that's mostly it. Basically since Flocks only use is for the systematic tracking of people for use by police and government agencies, it's a lot easier to get people to turn against it. There's just no upside to them that any individual would ever benefit from.
It's sad because if/when Flock dies the death of deserves, the software/infrastructure will likely just get sold off and reapplied to some other deployment scheme like Ring quietly forgoing the big Superbowl Ad.