CBS’ The Big Bang Theory proved that its narrow demo ratings win over American Idol in the 8-8:30 PM slot last week was no fluke. Last night, the hit CBS comedy (5.4/15 in adults 18-49, 16 million) was up 4% from its fast national result last week, finishing well ahead of Idol (4.8/14, 15.5 million) in the half-hour among adults 18-49. (Last week, the margin was 0.1) Big Bang also topped Idol in total viewers, adults 18-34 and adults 25-54. Additionally, the comedy tied the entire Thursday edition of Idol (5.4/15 in 18-49, 17 million) in 18-49 for the first time to finish No. 1 for the night. Versus last week’s fast nationals, Idol was down 6%. There was good news for Fox’s new drama The Finder (2.9/7), which was up a big 32% from last week. The Bones spinoff was probably aided by weaker competition at 9 PM, with no The Office and Grey’s Anatomy and Person Of Interest airing reruns vs. an originals last week, but the steady, double-digit growth is nevertheless impressive especially given the show’s underwhelming start.

News was not bad for another new series in its third week, CBS’ comedy Rob (3.5/9), which was down a tenth from its fast national last week and flat with the final. CBS aired drama repeats at 9 PM and 10 PM. NBC’s 30 Rock (1.6/4) was even with last week’s season low, while Parks And Recreation (1.7/4) was down 11% to a series low. Another 30 Rock original (1.9/5) aired at 9 PM, followed by an Up All Night rerun (1.4/3) and a new The Firm (1.0/3), which bounced back from last week’s series low, up a tenth. ABC aired reruns.