> So should the metric for that be total people that are part of a topic, or the % of total city population engaged in that topic? Ideally, both. You want to h

> So should the metric for that be total people that are part of a topic, or the % of total city population engaged in that topic? Ideally, both. You want to have a community with at least N people, but cities with a high % should rank higher. Could also account for the number of total meetup.com members in that place.