Mentors provide bespoke guidance. They take a personal interest in you. It's customized, rare and expensive.
Heroes live their lives in public, broadcasting their model to anyone who cares to look.
The internet has created a long tail of heroes. There are tens of thousands of musicians, artists, entrepreneurs, social leaders, politicians (okay, maybe not thousands of these), coders and colleagues to find and emulate. WWHD. What would my hero do?
I find heroes everywhere I look. I find people who speak to me over my shoulder, virtual muses, who encourage me to solve a problem or deal with a situation the way they would. This is thrilling news, because there are so many heroes, so freely available, whenever we need them.
For all the people out there using the fact that Jeff Bezos (or Jacqueline Novogratz or Husain Abdullah or Chris Anderson or Anne Jackson) won't be their mentor as an excuse for inaction, there are a dozen who realize that their example is enough.
Like a custom made suit, a mentor is a fine thing to have if you can find or afford it. But for the rest of us, heroes will have to do.