Shaun Connolly just joined us at Ringside, and he is already developing some interesting perspectives on the Social Web. Read his big dog pick...
To add my two cents, I think it is clear that Facebook is the big dog for Social Networking and Google is the big dog for the Social Web.
Facebook of course gets points for the rapid growth of their prime target social graph and extensive developer community - which are all targetted at making THEIR social network stronger.
Google gets points for trying to make Social a real part of the entire Web. The strong community they have built around Open Social is impressive. The ideas of Friend Connect open up social capabilitites to any website. These are efforts that make Social a part of the entire web.
Facebook has fought back. First by locking down Friend Connect from being a part of the Facebook community. Their current statements about moving to open source could put them into contention with Google in terms of "big dog" leadership of the Social Web. That will be a big leap for them to make, but I hope they do it. Social Networking is cool, but the Social Web could really change things in a dramatic way.