Ratings firm Nielsen this week introduced a new ratings tool dubbed Twitter TV Ratings. The new metric offers to gauge audiences' attitudes toward TV programming -- no matter where/how they watch. With second-screen viewing of traditional and non-traditional TV programming becoming increasingly popular, the ratings system offers a potentially more accurate test of a show’s popularity. Social media has so far befuddled advertisers. Twitter TV Ratings may be a good first step in analyzing engagement on a massive scale.