I don’t think addition is the correct operation. Perhaps we could say all of
- Bookcrossing ∩ Mediachest ≠ ∅
- Orkut ∩ Mediachest ≠ ∅
- Bitzi ∩ Mediachest ≠ ∅
- HotOrNot ∩ Mediachest ≠ ∅
or something more interesting if I actually knew set theory and notation.
Seriously though, lots of people realize that social networks can facilitate navigation, discovery, trust, filtering, communication and the like in many domains. Will people move on from sites that encourage building lists of “friends” for the sake of building such lists (and dating, I hear) to sites that use social networks to enhance other functions a la Mediachest or will the likes of Friendster and Orkut add more utility? Probably something else. Consider that
- Orkut has only scratched the surface of what a pure social networking service could offer. There are no collaborative filtering or recommendation features for starters. I don’t think Orkut is near an 80/20 sweet spot, or wherever diminishing returns set in for a pure social networking site.
- Sites with huge existing memberships haven’t added social networking to their offerings. Friends.yahoo.com does not exist.
- I’m forgetting stuff, but not the decentralized path. See FOAF and XFN. Atop which every value-add you can imagine (a miniscule subset of the total) will be built in the semi-near future, like by 2009.
Bitzi has had a very simple social network feature since May, 2001, “interesting bitizens”. Mine (and those interested in me) are currently listed on the right side of my bitizen page. We still haven’t built any features using these relationships, apart from an ignored popularity contest. Eventually. Before 2009.