Google is rumoured to be developing a social network search engine.With the explosion in social media content this could be highly useful for marketeers and advertisers.
For advertisers to establish what is going on about their brands in social media networks is challenging to say the least. Sure computers can do some of it for you but it requires human intervention and some creativity to work out how to capitalise on what is happening in particular networks.
http://www.shinyred.tv/2008/04/23/hide-n-seek-web-20s-killer-app/
What is clear though is that control of social media is impossible. Anyone can freely jump into a social media space and broadcast their messages to the world. While search tools might help guide the bewildered through social media networks, it will be very hard to develop ad campaigns which are genuinely interesting for people clustered around niches of mutual interest. PR online I think is going to be critical for major brands, to identify issues and engage with people within networks.