One of the great things about moving to Silicon Valley is that you're surrounded by all these people who've done it before. This place is an assembly line that takes a couple of twenty-somethings and walks you through everything you need to learn.
Our users are trapeze artists, high school football coaches - I got cornered by a couple of theoretical physicists who said Dropbox lets them collaborate across the world and share their experiments' results. They were raving about how it's driving their research.