“Initial analysis reveals that the Twitter TV audience for an episode is, on average, 50 times larger than the authors who are generating tweets,” says Nielsen.

“For example, if 2,000 people are tweeting about a programme, 100,000 people are seeing those tweets. This multiplier varies across programs, with early data showing the ratio of the audience to the authors generally decreases as the number of authors for an episode increases. This is due to the increasing overlap of followers for shows with a large number of Twitter authors, where a single follower is increasingly likely to follow multiple authors.”

It’ll surprise no-one to see that Breaking Bad tops the first published rankings, given the much-hyped and oft-discussed end to the show’s five-season run. The top five shows are below. The complete top ten is online here.

Nielsen says that Twitter conversation about live TV has grown dramatically in the US over the past two years. Citing its social TV measurement company SocialGuide, Nielsen says: “19 million unique people in the US composed 263 million tweets about live TV in Q2 2013 alone, a 24% year-over-year increase in authors and a 38% increase in tweet volume.”

But what does all this activity mean for advertisers and media owners? “We are just beginning to understand the dynamic relationship between social media and television,” says Beth Rockwood, senior vice president, market resources and ad sales research at Discovery Communications.

A recent study, commissioned by the Council for Research Excellence, found that social media is unlikely to draw new or infrequent viewers to an existing television show, although it suggested that social media may have a stronger role to play in building relationships with a show for existing viewers. Meanwhile, Nielsen’s Twitter Causation Study found a statistically causal influence indicating that a spike in TV ratings can increase the volume of tweets, and, conversely, a spike in tweets can increase tune-in.

But while the research work continues, there are those who see immediate advantages to the Twitter TV Ratings data. Bonin Bough, vice president, global media and consumer engagement at Mondel?z International, says: “Knowing in advance what the effective Twitter TV engagement is around key events is game-changing and will enable us to connect even more efficiently with our consumers.”

• Twitter, Facebook and other forms of second-screen engagement are the subject of a detailed special report in the next issue of Impact, the quarterly magazine of the Market Research Society. Issue 3 is published this week. Visit mrs.org.uk/impact to subscribe.