It probably didn’t matter what CBS filled the 8 p.m. Thursday time slot with during a brief rest for its “Survivor” franchise. The performance of “CSI” at 9 p.m. and “Without a Trace” at 10 have been so strong this season that they can make up for any dead weight.
   Good thing.
  The limited-run “Wickedly Perfect” reality show that debuted last night is a placeholder, and one with very little promise.
   The show, in which contestants compete to become the next Martha Stewart-like domestic goddess, averaged an unimpressive 3.0 18-49 rating for its hour-long premiere, according to Nielsen overnights.
   That in turn helped boost CBS’s two main competitors in the time slot, “The O.C.” and “Joey,” to their best ratings since early November.
   CBS still won the night easily with a 6.8 average rating, ahead of NBC’s 4.7. 
   Meanwhile, in encouraging news for NBC, the new comedy “Committed” held nearly 100 percent of “Joey’s” lead-in audience at 8:30, posting a 5.0 rating that was 0.5 ahead of its Tuesday premiere.
   “Perfect” averaged a mere 2.6 rating in its first half-hour. NBC’s “Joey” nearly doubled that with a 5.1 rating. It was way up from “Joey’s” last original episode, which averaged a series-low 4.0 on Dec. 12. 
   “Perfect” was well off of “Survivor: Vanuatu’s” season-long 7.4 average in the Thursday 8 p.m. slot. It did gain viewership in the second half-hour, rising to a 3.4 rating, but it still didn’t break the 10 million total viewers mark.
   Fox’s “The O.C.” also benefited from the watered-down competition. The show boasted a 3.3 average, 14 percent higher than for its last original episode on Dec. 12.
   “CSI” was the night's highest-rated show among viewers 18-49 with a 9.6 average rating. That helped CBS to a first place finish for the night with the 6.8 average rating and 18 share. NBC finished second at 4.7/12, Fox third at 2.5/6, ABC and UPN tied for fourth at 2.0/5, and the WB sixth at 1.2/3.
   CBS took the lead at 9 p.m. with “CSI’s” 9.6 average, followed by NBC’s 4.7 average for an hour of “Will & Grace.” UPN finished the hour third with a 2.1 average for “WWE Smackdown.”
   At 10 p.m. CBS led again, this time with a 7.7 average for “Without a Trace.” NBC was second with a 4.2 for an encore presentation of the new drama “Medium,” with ABC third with a 2.7 average for “Primetime.”
   CBS finished on top for the night among households with a 13.1 average rating and 20 share. NBC finished second at 7.1/11, ABC third at 4.5/7, Fox fourth at 3.8/6, UPN fifth at 3.4/5, and the WB sixth at 2.0/3.