When the fourth season of NBC’s “Community” aired in February, it pulled in 4 million viewers, which is roughly a quarter of the audience that tunes in to top hit sitcoms. Until recently, Nielsen numbers in that range might be the end of a series (think “Firefly,” “Jericho,” “Freaks and Geeks”). But on the night of the “Community” premiere, the show spawned two worldwide trending topics via Twitter — perhaps a more important metric today. Continue reading Should Nielsen Change How it Measures TV Audiences?