One of the most common and important activities in activity streams is sharing information. This is when a piece of interesting content, always the most interesting when it’s a link that points to the original information elsewhere on the network, is shared by someone. This shared information is placed into the activity streams of everyone in that person’s social graph. At this point, something interesting happens: That piece of Web or enterprise content becomes a social object.
via ebizq.net
Nice overview of technical background and cultural impact of social objects — and they’re applicability in the enterprise.