Here is an interesting piece for people in social netwroking space. Here is the best advice:
The other bit of advice that everyone in the room was eager to hear was how to build a user base, when users join social networks only when their friends are already using them. Mike Speiser, who founded talent competition social network Bix and sold it to Yahoo! (nasdaq: YHOO – news – people ) In 2006, said everyone does it the same way– by telling everyone at the start-up to send a link to the site to everyone in their address books. “There is no silver bullet–that’s the only way to do it.”