during the episode of 'the late late show with craig ferguson' on july 23 it was apparent that craig didn't care much for the audience. they kept 'ooh'ing and 'boo'ing at all the wrong times and it obviously got on his nerves, causing him to get up out of his desk and shake his fist at them!
this fist shaking incident either made him feel bad and now is trying to cover it up, or it was an inspiration to him for a new schtick. because since then he has turned it into a bit that he does where he threatens to shake his fist at the audience, when he does they even play silly music as he goes from one side of the audience to the other as the camera follows him. it quite funny because i have always enjoyed (and actually copied in real life) the way he shakes his fist: he doesnt move his whole arm, rather he shakes it at the wrist.