Not to sound too scathing in this, but from pouring through numerous interviews, Bill Murray movies, and certain sources, I have come to the conclusion that Bill Murray will not do GB3, due to the fact that he is basically remembered for Ghostbusters and nothing else. His last “good” movie was five years ago, and he has not done much as a star, save for a major role in Charlie's Angles. But it is my belief that Murray has blamed Ghostbusters all these years for destroying his potential in other starring roles.