If you want to get a feeling for Josh Elman’s career, just trace the history of modern social networks. Josh held increasingly senoir roles at RealNetworks, LinkedIn, Facebook, and Twitter. Now he’s now supporting the next generation of breakthrough entrepreneurs at Greylock Ventures. In his VC role, Josh sees a lot of pitches -- and he’s got a keen eye for the tricky balance that successful entrepreneurs need to strike: Listen in and take a journey through the recent past and exciting future of networked social experiences.