Federated Media's John Battelle posed this question to Twitter co-founder Evan Williams at the Web 2.0 Summit. Part of the answer, according to Williams, is that the company calculates a reputation score for every user.
While Williams -- who recently stepped down as Twitter's CEO to focus on product -- did not disclose specifics, he did share that each Twitter user has a reputation score, which the company uses internally as part of its Who to Follow formula. That score may eventually become part of Twitter's public-facing features, says Williams.
Reputation scores, and influence in particular, have become trendy subject matters in today's social media world. Startup Klout has developed an entire business around scoring social influence. A Twitter user's Klout score, for instance, could determine whether he or she gets special treatment from an airline or hotel.