Ashlee Simpson is determined to stay optimistic about her career, despite being booed by 72,000 people at the Orange Bowl half-time show in Miami last week. Simpson tells MTV News, "There was some booing that went on after the half-time show was finished. If they didn't like the performance--and that's what it was about--then sorry to them." The Oklahoma Sooners and the University of Southern California Trojans battled for the national college football championship at the Orange Bowl. Simpson speculated that it was the Oklahoma Sooners fans booing her because a film clip of her rooting for USC was shown...