Jell-O has taken the mood ring to an unhealthy level. The odd floating head reacts to the overall happiness of the people on twitter who follow it.
When Puddingface is happy all is right with the world. When PuddingFace senses a disturbance in the force an alarm sounds on the bottom of the page and PuddingFace starts to dispense with the Free pudding. Marketing ploy of odd floating head, or both.