HBO's John Oliver has found his late-night niche -- viral rants

Jimmy Fallon has musical numbers. Jimmy Kimmel has pranks. And now, HBO's John Oliver has found his own niche: Perfecting the art of the viral rant. The former "Daily Show" correspondent took a gamble when he launched his own late-night show this spring, but his rants about various topics -- climate change, General Motors, net neutrality -- every Sunday have kept him relevant in a crowded field. The 10 to 13 minute videos have taken off across the Internet every Monday morning, the day after "La...