nielsen ratings
(fast national numbers for thursday, march 31, 2011)

Here are the highlights of the 17 ad-sustained programs that aired in primetime on the broadcast networks last night:

FOX (16.43 million viewers, #1; adults 18-49: 5.2, #1) was the network to beat on Thursday thanks to a new "American Idol" (22.02 million viewers, #1; adults 18-49: 6.7, #1) and the reality special "Mobbed" (10.85 million viewers, #6; adults 18-49: 3.8, #3). Said numbers marked the most-watched unscripted telecast to follow an "Idol" episode in over two years (since "Hell's Kitchen" on 1/29/09).

ABC (8.89 million viewers, #3; adults 18-49: 3.1, #2) then took home second place with new episodes of "Wipeout" (6.34 million viewers, #9; adults 18-49: 1.9, #9), "Grey's Anatomy" (12.72 million viewers, #3; adults 18-49: 4.8, #2) and "Private Practice" (7.60 million viewers, #8; adults 18-49: 2.7, #7).

Next up was CBS (12.10 million viewers, #2; adults 18-49: 2.9, #3) with the post-NCAA return of "The Big Bang Theory" (11.70 million viewers, #5; adults 18-49: 3.6, #4), "Rules of Engagement" (8.18 million viewers, #7; adults 18-49: 2.3, #8), "CSI: Crime Scene Investigation" (12.49 million viewers, #4; adults 18-49: 2.8, #T5) and "The Mentalist" (13.86 million viewers, #2; adults 18-49: 2.8, #T5).

Meanwhile, NBC (2.38 million viewers, #4; adults 18-49: 1.1, #4) offered up its mix of "Community" (2.29 million viewers, #12; adults 18-49: 0.9, #15), "Perfect Couples" (2.14 million viewers, #14; adults 18-49: 1.0, #T12), "The Office" (3.16 million viewers, #10; adults 18-49: 1.5, #10), "Parks & Recreation" (2.39 million viewers, #11; adults 18-49: 1.1, #11), "30 Rock" (2.16 million viewers, #13; adults 18-49: 1.0, #T12) and "Outsourced" (2.12 million viewers, #15; adults 18-49: 1.0, #T12) - all repeats, save for "Couples," which hit a series low without first-run bookends.

And finally, repeats of "The Vampire Diaries" (1.20 million viewers, #16; adults 18-49: 0.5, #16) and "Nikita" (1.15 million viewers, #17; adults 18-49: 0.4, #17) on The CW (1.18 million viewers, #5; adults 18-49: 0.4, #5) rounded out the night.

Week-to-week changes (adults 18-49): Grey's Anatomy (33.30%), American Idol (8.10%), Private Practice (0.00%), The Big Bang Theory (-5.30% vs. 3/10/11), The Mentalist (-6.70% vs. 3/10/11), CSI: Crime Scene Investigation (-9.70% vs. 3/10/11), Wipeout (-13.60%), Rules of Engagement (-17.90% vs. 3/10/11), Perfect Couples (-37.50%).

In late-night metered market ratings (via NBC's press release):

In Nielsen's 56 metered markets, household results were: "The Tonight Show with Jay Leno," 2.5/6; CBS's "Late Show with David Letterman," 2.9/7; and ABC's combo of "Nightline," 3.1/7; and "Jimmy Kimmel Live," 1.3/4.

In the 25 markets with Local People Meters, adult 18-49 results were: "The Tonight Show with Jay Leno," 0.9/4; "Late Show," 0.8/4; "Nightline," 1.1/4; and "Jimmy Kimmel Live," 0.5/3.

At 12:35 a.m., "Late Night with Jimmy Fallon" (1.3/4 in metered-market households) trailed CBS's "Late Late Show with Craig Ferguson" (1.5/5). In the 25 markets with Local People Meters, "Late Night" (0.5/3 in 18-49) tied "Late Late Show" (0.5/3).

At 1:35 a.m., Last Call with Carson Daly" averaged a 0.7/3 in metered-market households and a 0.3/3 in adults 18-49 in the 25 markets with local people meters.

Here are the highlights of the 13 ad-sustained programs that aired in primetime on the broadcast networks one year ago (4/1/10):

CBS (12.74 million viewers, #1; adults 18-49: 3.0, #1) snagged the top spot on Thursday thanks to a new "Survivor: Heroes vs. Villains" (11.08 million viewers, #3; adults 18-49: 3.5, #T1) followed by a flipped editions of "The Mentalist" (13.93 million viewers, #1; adults 18-49: 2.8, #T3) and "CSI: Crime Scene Investigation" (13.21 million viewers, #2; adults 18-49: 2.8, #T3).

ABC (7.55 million viewers, #2; adults 18-49: 2.5, #2) then had to settle for the silver with new episodes of "FlashForward" (5.07 million viewers, #9; adults 18-49: 1.5, #11), "Grey's Anatomy" (9.75 million viewers, #4; adults 18-49: 3.5, #T1) and "Private Practice" (7.83 million viewers, #6; adults 18-49: 2.8, #T3).

Next up was FOX (7.20 million viewers, #3; adults 18-49: 2.3, #3) with the return of "Bones" (8.44 million viewers, #5; adults 18-49: 2.4, #6) and "Fringe" (5.97 million viewers, #7; adults 18-49: 2.2, #8).

Meanwhile, NBC (4.44 million viewers, #4; adults 18-49: 1.9, #4) offered up one-hour repeats of "The Office" (4.04 million viewers, #10; adults 18-49: 1.6, #10), another "The Office" (4.02 million viewers, #11; adults 18-49: 1.8, #9) and a new "The Marriage Ref" (5.26 million viewers, #8; adults 18-49: 2.3, #7).

And finally, new episodes of "The Vampire Diaries" (2.80 million viewers, #12; adults 18-49: 1.3, #12) and "Supernatural" (2.39 million viewers, #13; adults 18-49: 1.1, #13) on The CW (2.60 million viewers, #5; adults 18-49: 1.2, #5) rounded out the evening.

Source: Nielsen Media Research