You know how social media allows to richer conversations and sharing than email? But you don't always want to conduct all your internal business in public, or have confidential information living on LinkedIn or facebook, even if it is in a private group. Enter Yammer, a business-oriented social network designed to be used in-house by organizations. It supports creating a true internal Community of Practice and integrates with everything from MS SharePoint to your email to Google to the public socnets.
In other words, it looks really cool. Anyone in the association space using it? I could see it being vital to an organization with large numbers of remote staff.