I know, I know, it's old news already but I really like what Ross Mayfield has to say about Yahoo's Social Search Act II

Mayfield says that Yahoo, when unveiling their new, My Web 2.0, sees search in a 3 stage evolution (so far)

• Act I: Public (e.g. Web Search)
• Act II: Personal (e.g. Desktop Search)
• Act II Social (e.g. search communities)

I think we see it the same way.  We took plain vanilla search and first made it customizable per user or per web publisher (personal).  From here, as we build out our network, our community, we envision numerous ways to evolve into Social Search.  The key here is providing useful tools to service the community, not building community to service to tools.