Reality powerhouses 'Wipeout' and 'Big Brother' went head-to-head tonight, giving their respective networks a split. ABC took the 18-49 demographic crown (1.8/6, 6.308 million), while CBS settled for a victory in total viewers.

Actually, for the first time in the summer, Spanish-language Univision (2.1/7, 4.771 million) took the true 18-49 crown with a full night airing of 'Premios Joventud 2010 (2010 Youth Awards).' Only ABC and CBS scored more total viewers.

Fox (1.5/5, 4.574 million) is down this season, but not yet out with the struggling 'So You Think You Can Dance.' The reality competition is well off its mark from last season, which could be a response to the format changes implemented at the beginning of the season, or more recently the plague of injuries that have been impacting virtually every aspect of the show.

NBC (1.0/3, 2.913 million) switched up their schedule in anticipation of the fall season, and saw improvements in most key time slots, while the CW (0.5/2, 1.578 million) again just threw two hours of vampires at their audience.

8:00

CBS had a slight demo lead in the first half of the hour with 'Big Brother' (2.4/9, 7.047 million), but 'Wipeout' (2.5/9, 7.768 million) grew nearly 20 percent within its own hour to claim the top spot of the night for ABC. 'Glee' (1.2/4, 3.601 million) slipped a tenth in the 18-49 demo on Fox against the heightened competition.

NBC was in repeats, shifting '30 Rock' (0.8/3, 2.388 million) to its new digs for the fall as 'Community's' (0.8/3, 2.414 million) lead-out, and should be pleased to see 'Rock' bring its audience with it. The half-hour improved 19 percent in total viewers from last week's 'Parks & Recreation' repeat, while staying even in the demo. 'The Vampire Diaries' (0.6/2, 1.646 million) was even for the CW.

9:00

'So You Think You Can Dance' (1.9/6, 5.548 million) slipped another 10 percent in the demo, and 7 percent in viewers with (Spoiler alert!) the second results show in a row that rendered viewer voting irrelevant due to contestant injuries. This allowed ABC's renewed 'Rookie Blue' (1.8/6, 6.446 million) to narrow the demo gap considerably. The police drama reversed trend and rose 12 percent in the demo from last week.

CBS managed to edge out 'Dance' in total viewers for the hour with a repeat of 'CSI: Crime Scene Investigation' (1.4/5, 6.703 million). The comedy switch-up at NBC benefited both shows, as 'Parks & Recreation' (1.0/3, 2.486 million) gained 20 percent in the demo and 22 percent in total viewers, thanks to the stronger lead-in of 'The Office' (1.2/4, 2.972 million). The CW and 'Moonlight' (0.5/2, 1.511 million) just kept doing what they do. It is interesting, though, that 'Moonlight' repeats are outperforming many of the CW's own shows this summer ('90210,' 'Gossip Girl,' 'One Tree Hill,' 'Life Unexpected').

10:00

'The Mentalist' (1.5/5, 7.422 million) stayed strong for CBS, while 'Boston Med' (1.3/4, 4.709 million) split its own difference. The medical reality series was up a tenth in the demo, while losing 6 percent in total viewers from last week.

NBC abandoned their full night of comedy, perhaps after the poor performance of the 'Community' marathon last week, and shifted repeats of 'Law & Order: SVU' (1.1/4, 3.609 million) to the 10PM hour. The hour improved for the Peacock by a tenth in the demo, and a whopping 41 percent in viewers to still come in last place. Remember when NBC's Thursday night lineup was untouchable?


Adults 18-49




Below is the format we use for showing the ratings data with a quick explanation of each part
Example: 'Show' (Demo/Share, Viewers+SD) [Network-Time]

Show - The name of the show. (R) indicates a repeat. (S) indicates a special presentation. (M) indicates a movie.
Demo - The percentage of adults aged 18-49 tuned to this show. This is the demographic advertisers desire.
Share - The percentage of adults 18-49 households with their televisions on who are turned to this show.
Viewers+SD - The total viewers including both live viewers and DVR viewers who watched the program the same day (generally by 3AM). DVR penetration has reached about 24 percent of American households
Network - The network the show aired on.
Time - The show's scheduled start time (this can get skewed for sporting events or other live programming).

Nielsen compiles their ratings from randomly selected representative groups of households. Overnight ratings are tabulated by tracking the channels that are on during each time period in those houses. As such, if a live event interrupts or delays the start of a program in certain areas, this data will not reflect those changes. Also, if a local affiliate chooses not to run a network's program at the scheduled time for some reason, this change will also not be represented. Thus, these figures can be skewed and should only be used as a general guideline. We will do our best to alert you when situations that could affect the accuracy of these figures occurs.

Our thanks to TV by the Numbers for their figures and estimates. If you have any questions about the ratings or what it all means, feel free to hit us up in the comments. We'll be here every day for you.

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