MBA students are generally more risk averse than the average entrepreneur. An MBA is helpful if you aren't sure what you want to do, because you can meet people from all over the world from different industries and different functions. It also helps with presentation and speaking skills (although some people take it too far and come across as arrogant as some of the other answers noted). If you know you want to be a product manager and know what area of technology you want to focus on, an MBA would not be as helpful as direct experience.
