"Laurent Eschenauer, one of the OneSocialWeb developers, says his project and Diaspora share the goal of providing a “free, open and decentralized alternative to the social networking silos that are Facebook and Twitter.” He says he hopes that Diaspora looks to work cooperatively with his project, rather than “reinventing the wheel."

...

"Both OneSocialWeb and Appleseed share the same problem: getting enough users to make users want to sign up — the so-called network effect where a network gets exponentially more useful as it gets bigger. (Think of the fax machine as an example — two fax machines in the world aren’t very useful, but your fax machine becomes much more useful when there are 1,000 of them, and even more valuable when there are 10 million.)"

...

"Users don’t have to choose to stop using Facebook or Twitter and will be able use the Diaspora client to use those all those services in one place — much like Friendfeed currently does. But when Diaspora knows that the person you are trying to communicate with also has Diaspora, it will use peer-to-peer, encrypted methods to send that message. And as more and more people start using the free software, they’ll slowly find themselves weaned from for-profit services, according to Moglen."

I think if the various social networks coming up interoperated, on some significant set of features, it would be good for all of them and all of us.

If service A has Ua users then the value of A is Ua^2 (or whatever). If B has Ub its value is Ub^2. If they interoperate then the value of both approach (Ua+Ub)^2. E.g. 3^2 = 9 and 4^2 = 16, or (3+4)^2 = 49. As service A adds users, services A and B both enjoy an increase in the value of their networks.

Edit: math notation.