As social media grows more popular, it’s increasingly becoming a way for industries, companies and brands to figure out what the cultural zeitgeist is thinking — and from there, to recommend other things consumers might like. Wharton operations and information management professor Shawndra Hill has extensively studied how social TV — i.e., people contributing or consuming commentary about their favorite programs — can be used by Hollywood and advertisers to better reach their target demographics. In this interview, she discusses her method and findings, and also responds to a recent announcement by Nielsen that it will now include demographic information as part of its Twitter TV ratings service. That service offers data that gauge which shows are generating the most chatter on the social network. An edited transcript of the conversation appears below. Knowledge at Wharton: Many people today tweet to provide commentary as they are watching TV shows.…