But like the best empire builders, he was both very determined and very skeptical. It’s like [former Intel CEO] Andy Grove says, ‘only the paranoid survive.

Revenues were, according to well-informed sources, more than $550 million for 2009—up from less than $300 million in 2008. That represents a stunning growth rate of almost 100 percent. The same sources say that the company could exceed $1 billion in revenue in 2010.

This thrilled Zuckerberg, whose primary measure of the service’s success was how often users returned.

In Friendster's wake, a throng of social networking sites blossomed in San Francisco attempting to duplicate its appeal. Each tackled the idea of connecting people in a slightly different way. One was Tickle, a service which, on observing Friendster’s broad-based appeal, altered its own service, which had previously been based on self-administered quizzes and tests. Two of the other new social sites—LinkedIn and Tribe.net—were founded by friends of Abrams.

By early 2004 Tickle had become the second-largest social network after Friendster, with two million members actively connected to others and exchanging messages.

It’s the simplest way to communicate, ... There’s just so much info that needs to be communicated to dispatch.