Nielsen Holdings NV , the television viewership measurement company, said on Monday it will partner with Twitter to publish a new set of ratings that measure chatter on Twitter about TV programming.
The new measurement, dubbed the "Nielsen Twitter TV Rating," seeks to tap into the stream of viewer commentary and armchair musings generated on "second screens" - the smartphones and tablets perched on Twitter users' laps while they watch, say, Monday Night Football or the latest episode of "Homeland" on their TVs.
The new ratings, to be launched next fall, arrive at a moment when media and advertising industry executives say they are observing a shift in TV viewing habits that include the rise of "second screen" use.
But significant questions remain for advertisers over how best to interpret the data and whether a Twitter ratings system is meaningful at all.
In September, Nielsen ratings showed that TV viewership for Viacom Inc's MTV Video Music Awards, which coincided with the Democratic National Convention, plummeted by more than 50 percent from a year ago.
Yet social media chatter tripled, according to the research firm Trendrr.
Brad Adgate, an analyst at Horizon Media, said advertisers will view the Twitter ratings as a useful layer of information about a show's popularity, but it is "not going to be close to the currency" of existing ratings metrics.
"It lets producers and creative directors know if the storyline is working, like a huge focus group," Adgate said.
"But I don't think you can translate comments to ratings for a show. Right now I think the bark right now is bigger than its bite.
" The new ratings will measure the number of people discussing a show on Twitter, as well as those who are exposed to the chatter, to provide the "precise size of the audience and effect of social TV to TV programming," Nielsen said.
"As the experience of TV viewing continues to evolve, our TV partners have consistently asked for one common benchmark from which to measure the engagement of their programming," Chloe Sladden, Twitter's vice president of media, said in a post on the company blog on Monday.
"This new metric is intended to answer that request, and to act as a complement and companion to the Nielsen TV rating."
Mark Burnett, executive producer of NBC's hit "The Voice," argued that advertisers should value programs that can attract a high level of social media engagement from viewers.
Deeply embedded social media elements, such