nielsen ratings
(fast national numbers for monday, september 20, 2010)

Here are the highlights of the 13 ad-sustained programs that aired in primetime on the broadcast networks last night:

The season premieres of "Dancing With the Stars" (21.00 million viewers, #1; adults 18-49: 4.9, #1) and "Castle" (11.17 million viewers, #6; adults 18-49: 2.8, #9) helped ABC (17.73 million viewers, #1; adults 18-49: 4.2, #1) open the 2010-11 season on top.

CBS (11.92 million viewers, #2; adults 18-49: 3.8, #2) then had to settle for second place with the respective launches of "How I Met Your Mother" (8.78 million viewers, #8; adults 18-49: 3.6, #7), "Rules of Engagement" (8.33 million viewers, #9; adults 18-49: 3.1, #8), "Two and a Half Men" (14.50 million viewers, #2; adults 18-49: 4.8, #2), "Mike & Molly" (12.24 million viewers, #4; adults 18-49: 3.9, #4) and "Hawaii Five-0" (13.83 million viewers, #3; adults 18-49: 3.8, #5).

Next up was NBC (8.40 million viewers, #3; adults 18-49: 2.8, #3) with the return of "Chuck" (6.06 million viewers, #11; adults 18-49: 2.1, #11) followed by the bows of "The Event" (11.19 million viewers, #5; adults 18-49: 3.7, #6) and "Chase" (7.94 million viewers, #10; adults 18-49: 2.5, #10).

"The Event's" debut topped every airing on Monday nights last season for the Peacock, save for the Olympics and the first episode of "The Jay Leno Show." Same for "Chase," although that's limited to the 10:00/9:00c hour.

Meanwhile, FOX (7.30 million viewers, #4; adults 18-49: 2.7, #4) served up the season premiere of "House" (10.54 million viewers, #7; adults 18-49: 4.2, #3) and the debut of "Lone Star" (4.06 million viewers, #12; adults 18-49: 1.3, #12).

Said launch of "Lone Star" came in below every first-run airing of previous time period holders "Lie to Me," "24" (low: "Lie to Me's" December 14 episode with a 2.2 rating in the key demographic).

And finally, new episodes of "90210" (2.16 million viewers, #13; adults 18-49: 1.0, #14) and "Gossip Girl" (1.87 million viewers, #14; adults 18-49: 1.1, #13) on The CW (2.01 million viewers, #5; adults 18-49: 1.0, #5) rounded out the evening.

In late-night metered market ratings, ABC's "Nightline" (3.1/7) and CBS's "Letterman" (3.1/8) took top honors ahead of NBC's "Leno" (2.8/7). Rounding out the night then were "Kimmel" (1.5/5) on ABC "Ferguson" (1.4/5) on CBS and "Fallon" (1.3/5) and "Daly" (0.7/3) on NBC.

Here are the highlights of the 14 ad-sustained programs that aired in primetime on the broadcast networks one year ago (9/21/09):

FOX (16.50 million viewers, #1; adults 18-49: 6.5, #1) kicked off the 2009-10 season with a monster start for "House" (15.76 million viewers, #3; adults 18-49: 6.2, #2) followed by a second hour of "House" (17.25 million viewers, #2; adults 18-49: 6.9, #1).

CBS (12.01 million viewers, #3; adults 18-49: 4.0, #2) then offered up the openers to "How I Met Your Mother" (9.21 million viewers, #8; adults 18-49: 3.5, #7), "Accidentally on Purpose" (8.99 million viewers, #9; adults 18-49: 3.2, #8), "Two and a Half Men" (13.59 million viewers, #5; adults 18-49: 4.4, #4), "The Big Bang Theory" (12.83 million viewers, #6; adults 18-49: 4.6, #3) and "CSI: Miami" (13.73 million viewers, #4; adults 18-49: 4.3, #5).

Next up was ABC (14.83 million viewers, #2; adults 18-49: 3.5, #3) with the two-hour season premiere of "Dancing With the Stars" (17.53 million viewers, #1; adults 18-49: 4.1, #6) and the return of "Castle" (9.43 million viewers, #7; adults 18-49: 2.3, #11).

Next up was NBC (5.90 million viewers, #4; adults 18-49: 2.4, #4) with the season premiere of "Heroes" (6.27 million viewers, #10; adults 18-49: 2.8, #9), a second hour of "Heroes" (5.78 million viewers, #11; adults 18-49: 2.7, #10) and the start of week two of "The Jay Leno Show" (5.67 million viewers, #12; adults 18-49: 1.8, #12).

And finally, new episodes of "One Tree Hill" (2.48 million viewers, #13; adults 18-49: 1.2, #13) and "Gossip Girl" (2.09 million viewers, #14; adults 18-49: 1.0, #14) on The CW (2.28 million viewers, #5; adults 18-49: 1.1, #5) rounded out the night.

Source: Nielsen Media Research