A living legend, he's been called "the voice of Wall Street." Barron's recently called him "the most consequential banker of his generation." In a 2010 profile, the New York Times called him "America's least-hated banker." Jamie Dimon, 70, has been CEO of JPMorgan Chase for 20 years and has no plans to retire just yet. The bank's $777-billion market value makes it the biggest bank in the world — larger than Bank of America, Wells Fargo and Citigroup, its three main competitors, combined.