Facebook is number 1 in the social market, at least for now, and is the glaring missing social networking service from those that have joined Google's OpenSocial network. Here's what I wonder: do all of the folks combined that now support OpenSocial, MySpace, Plaxo, etc. combined come close to being as big as Facebook? My guess is that all of the OpenSocial participants combined still wind up being a very far second to number 1 -- this isn't based on anything except for my general experience about competition. I would state that OpenSocial is evolutionary and reactionary based on competing with number 1 rather than being fully revolutionary; after all, isn't this exactly what Facebook did that was considered so revolutionary when they did it and no one else had?
Maybe I'm wrong, but then, why are you still interacting with me on Facebook in their walled garden?