What characteristics of the commoners is Marullus pointing out when he reminds them they once cheered Pompey?
Murellus is pointing out how the commoners change their allegience easily. They once cheered for Pompey--waiting at the city gates in anticipation for victory. Now that Pompey has been defeated by Caesar, the commoners are easily swayed to Caesar's favor. Murellus is pointing out their inconsistencies as a country.