NBC loses Thursday night viewers to CBS and Fox -- The Peacock's primetime lineup is no longer Must See TV, thanks to strong ratings and viewer interest in shows like ''CSI'' and ''The O.C.''

By Lynette Rice
Updated November 19, 2004 at 05:00 AM EST

NBC set a record on Nov. 4, but the Peacock net isn’t preening: The night marked its lowest Thursday sweeps performance since 1987. The depressed ratings are the culmination of a season-long decline: NBC’s Friend-less Thursday is off 13 percent since last year and 11 percent since September. Most of the damage has been inflicted by CBS’ top 10 staples Survivor, CSI,and Without a Trace (which scored a 21 percent edge over NBC among adults 18 to 49 on Nov. 4), but Fox delivered the most recent blow. The season 2 debut of the new-to-Thursday O.C. at 8 p.m. gave Fox its first 18-to-34 win over NBC since 1994.

”Beating NBC was something we never expected,” says Fox Entertainment president Gail Berman. ”We’ve just begun to fight.” That fighting spirit has worked for CBS — now No. 1 among total viewers on Thursday night — which commands spectacular ad rates once reserved for Must See TV (as of early this fall, an estimated $412,000 for a 30-second spot during Survivor and $374,000 for a CSI ad, according to Advertising Age). Says CBS head of scheduling Kelly Kahl: ”Five years ago, we had Diagnosis Murder. Now we have CSI. We went from worst to first.”

Where does that leave NBC? With Joey, Will & Grace, The Apprentice, and ER all down (season-to-date, they rank 21st, 23rd, 14th, and 9th, respectively), the Peacock’s feathers are at least temporarily ruffled. ”NBC has gone through this before,” acknowledges the net’s entertainment president, Kevin Reilly. ”There is a distinct audience that watches nothing except Thursdays on NBC.” What if other nets keep hauling out big guns? ”NBC will be important,” says media analyst Tim Spengler. ”But from now on, there’ll be other players. You can’t ignore that from an ad-buying standpoint.”