Fast National ratings for Thursday, June 23, 2011.
 
ABC premiered its summer Thursday lineup to strong "Wipeout" numbers, a good "Expedition Impossible" premiere and a somewhat soft return for "Rookie Blue." The less-than-impressive "Rookie Blue" ratings helped repeats-laden CBS secure a Thursday night split.
 
Among adults 18-49, ABC averaged a 2.1 rating for the night, beating FOX's 1.5 rating in the key demographic. CBS was third with a 1.4 rating, with NBC's 0.8 rating and the 0.4 rating for The CW well off the pace.
 
Overall, though, CBS averaged an estimated 7.37 million viewers to go with a 4.8 rating/8 share. That left ABC in second with a 3.9/7 and nearly 6.8 million viewers, topping the 3.0/5 and 4.78 million viewers for FOX. NBC was well back in fourth with a 1.4/2 and 2.17 million viewers. The CW averaged a 0.6/1 and 911,000 viewers.

8 p.m. - In a competitive 8 p.m. hour, ABC's "Wipeout" had its summer return and averaged 7.47 million viewers and a 2.3 rating among adults 18-49. CBS' "Big Bang Theory" and "Rules of Engagement" averaged 6.42 million viewers for second overall. FOX's "So You Think You Can Dance" averaged 6.32 million viewers for third and a 1.9 key demo rating (down from last week) for second. NBC's "Community" and "30 Rock" finished fourth with 2.23 million viewers, while The CW's "The Vampire Diaries" averaged 871,000 viewers.
 
9 p.m. - CBS moved into first overall with 7.68 million viewers for "CSI: Crime Scene Investigation" in the 9 p.m. hour. ABC's premiere of "Expedition Impossible" averaged 7.05 million viewers for second and won the hour with a 2.3 key demo rating. FOX's "Glee" averaged 3.23 million viewers, which bettered the 2.32 million for NBC's "The Office" and "Parks and Recreation." On The CW, "Nikita" averaged 950,000 viewers.
 
10 p.m. - "The Mentalist" averaged 8.01 million viewers to win the 10 p.m. hour for CBS overall. ABC's return of "Rookie Blue" averaged 5.88 million viewers and won the hour with a 1.6 key demo rating. NBC's new "Love Bites" averaged 1.99 million viewers and a 0.8 demo rating, both down from last week.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.