Forbes magazine unveiled its "World's Most Powerful People" list on Thursday ranking U.S. President Barack Obama as the most powerful person in the world this year, among 7.1 billion people taken into consideration.This year's list included head of governments, businessmen and even the magazine added famous Mexican drug lord Joaquin "El Chapo" Guzman Loera, the head of Mexico's Sinaloa cartel and one of the most wanted drug traffickers in the world.