I've been wanting to write a paper like this for several years. It uses visualisation techniques to determine social roles in online discussions. In this case they can detect what they call "Answer People". I've been following the work of Marc Smith since I listened to a podcast Catalyzing Collective Action on the Net (2004-02-11) from the O'Reilly Emerging Technology conference. I even bought his book (1999) Communities in Cyberspace. I think I can apply these techniques to a large collection I have.