The idea of a "social" bittorrent client is not new in the sense that the Tribler client defines itself as a "social application" - see: http://www.tribler.org/.

I think tribler defines "social" as those who you have social ties to rather than those who you are geographically close to. It thus leverages "socialness" for security rather than speed.

I think the tribbler's definition is correct. In the modern era, we often don't have social ties to those geographically close to us. Duality should simply be called a "geo-aware" client - not a bad thing.