There actually is something I think Google Buzz could do well that it doesn't do yet: Collecting all the strands of all your social networks into one searchable database. Not quite like what Friendfeed does; what I'm suggesting instead is that Google should drop out of the social networking game altogether and instead work as a personal social networking archive. Twitter's search doesn't go backward very well at all, and trying to find anything on Facebook's mail system is a joke (which is one of many huge problems with the idea of Facebook getting into the public e-mail game, as some are theorizing.)
But in lighter social networking news, Pete Warden has analyzed the Seven Facebook Regions of the United States of America. You can see the overall map to the left here (click to enlarge), but you'll want to go and read his blog for more analysis. (I especially like "Mormonia," which is the only region that is completely surrounded by another region.) He calls Seattle's region, Pacifica, "the most boring of the clusters."