"Fanboy" or not, if you really think about it, Jobs's achievements (Apple computer, Mac OS, Pixar, iPod, iPhone, iPad) are significant in that they have inspired or facilitated the creation of countless other significant achievements, from music to movies, industrial design, software, publishing, broadcasting, etc. And if they aren't involved in the production, they're revolutionizing the delivery (iTunes/iPod/iPad/iPhone).<p>As impressive as Facebook's user base is, it's significance sort of begins and ends with Facebook, and that significance may or may not be positive. It helps us keep in touch with more acquaintances and friends, record our social interactions (photos/wall), but when you leave the site, does Facebook continue to impact your life? Maybe, at best, it helped organize a larger group of volunteers for a breast cancer walk, but that seems to be more of a byproduct of having 500 million users.