Yammer, the San Francisco startup that offers a solid enterprise-grade microsharing and realtime communications service, is expanding its executive team after successfully closing a Series B funding round to the tune of $10 million earlier this month. The company made one internal promotion, appointing co-founder and VP of Technology Adam Pisoni to CTO. In addition, Yammer recruited David Satterwhite to lead its sales efforts, while Steve Apfelberg was brought in as VP of Marketing.