Sone is a Social Network plugin for Freenet. And as “social network” is a rather unspecific term, yes—it’s a Facebook clone on top of Freenet. With the current version (0.2-RC2) you can already post updates, reply to other people’s updates, and like posts and replies. The list of currently known Sones is retrieved from the node’s web of trust plugin so make sure to get the very latest version of that, too.
The key for the current version is