Who is Dustin Moskovitz from The Accidental Billionaires: The Founding of Facebook: A Tale of Sex, Money, Genius and Betrayal and what is their importance?

Dustin Moskovitz roomed with Mark Zuckerberg at Harvard. After Facebook took off, Zuckerberg recruited Moskovitz to be director of programming. Dustin was given a percentage of the company for his efforts.