Fast National ratings for Thursday, August 5, 2010.

 
Paced by a strong "Big Brother" episode and the usual solid procedural performances, CBS won Thursday night overall and tied with a "Rookie Blue"-boosted ABC in the young adult demos.
 
Among adults 18-49, ABC and CBS both averaged a 1.6 rating, beating the 1.4 rating for FOX in the key demographic. NBC's 1.1 rating was fourth, with The CW's 0.4 rating trailing. 
 
Overall, CBS averaged an estimated 6.68 million viewers to go with a 4.2 rating/8 share. ABC's 3.7/7 came in a close second. FOX's 3.0/5 was third. NBC's 2.0.4 finished fourth, comfortably ahead of the 0.8/1 for The CW.
 
"Big Brother" delivered a 4.2/8 for CBS in the 8 p.m. hour, also winning with a 2.4 demo rating, the night's best. ABC's repeat of "Wipeout" averaged a 3.8/7 for second. FOX's "Glee" repeat finished third for the hour, beating the 1.8/3 for NBC's "Community" and "30 Rock." The CW's "Vampire Diaries" repeat had a 0.8/2 for fifth.
 
ABC's "Rookie Blue" won the 9 p.m. hour for ABC with a 4.2/7, also tying for first in the demo with a 1.8 rating. CBS' "CSI: Crime Scene Investigation" repeat had a 3.9/7 for second. FOX's "So You Think You Can Dance" was third overall with a 3.4/6 and tied for first in the demo. NBC's "The Office" and "Parks and Recreation" repeats were fourth with a 1.7/3, still beating The CW's "Moonlight" encore.
 
A repeat of "The Mentalist" won the 10 p.m. hour for CBS with a 4.6/8. ABC's "Boston Med" was second with a 3.3/6 and tied with CBS for first in the demo. NBC's repeat of "Law & Order: Special Victims Unit" was third.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.