Prime Time Preliminary Tuesday Ratings

"Opportunity Knocks" on ABC debuted to disappointing numbers, while CBS' "The Mentalist" got off to a solid start. Fox won the night in 18- to 49-year-olds with "House" and "Fringe," although the shows were down a respective 12% and 18% from last week. CBS captured the night in total viewers with 14.9 million viewers, its largest Tuesday audience since 2001.

	8	9	10
3.7 / 10	Opportunity Knocks 1.8 / 5 6.6 mil	Dancing With the Stars 4.7 / 12 18.2 mil
3.3 / 9	NCIS 3.5 / 10 17.7 mil	The Mentalist 3.5 / 9 15.5 mil	Without a Trace 2.8 / 7 11.4 mil
4.5 / 12	House 4.9 / 14 12.1 mil	Fringe 4.2 / 10 9.7 mil	No Programming
3.2 / 8	The Biggest Loser: Families 2.9 / 8 7.2 mil		Law & Order: SVU 3.7 / 10 9.5 mil
1.2 / 3	90210 1.5 / 4 3 mil	Privileged 0.9 / 2 1.9 mil	No Programming

Source: Nielsen Media Research

*Ratings are specified in the 18-to 49-year-old demographic and viewership in P2+.

A note about ratings: Ratings are expressed as percentages of Nielsen's estimated 112.8 million U.S. television households. The first number, the rating, is a percentage of households tuned into a specific program at a specific time.

The second number, the share, is a percentage of households with televisions in use tuned into that same program. For example, if a show obtains a 10.2/16, this means that 10.2% of all U.S. households tuned into the program at some point during the broadcast. Meanwhile, 16% of all households watching television during the time period viewed the program at some point. Ratings are broken down further by demographic, as networks sell advertising time based on the makeup of the audience.