Numbers make the world go 'round in TV, especially ratings numbers.

The ones that are used to sell advertising target specific demographics groups, or demos. And the most important measure in local TV is the rating among viewers in the 25-54.

Those numbers are out this week for the four-week January rating period.

With the February "sweeps" altered by the Olympics on NBC, and the fact that other networks are counter-programming with a lot of reruns, January is a little more important this year than in non-Olympic years.

At 10 p.m., Channel 4 had a 4.8 rating in the demo, followed by Channel 12 with a 4.3, Channel 6 with a 3.3 and Channel 58 with a 3.4.

In January 2009, Channel 4 and 12 were tied with a 5.3 rating, Channel 6 had a 3.7, and Channel 58 had a 2.5.

The rating is a percentage of viewers in that demographic group.

At 9 o'clock: This year, the 9 p.m. hour is particularly interesting, since January was the last full month of the failed Jay Leno prime-time show.

On weeknights, Channel 12 won the hour with a 4.5, followed by Channel 58 with a 4.4, Channel 6's hour of news with a 4.3 and Channel 4's airing of Leno with a 3.9.

In January 2009, Channel 12 led with a 5.5, Channel 6's news had a 4.8, Channel 58 had a 4.5 and Channel 4 had a 4.2.

After the Olympics, NBC is going back to rotating 9 p.m. programs, and we'll have to wait for the May ratings period to measure a "normal" month -- as if anything in TV is normal these days.

On TV: The Hollywood Reporter's Roger Friedman blogs the possibility that Conan O'Brien just may try to upstage Jay Leno's return to "The Tonight Show" next week by announcing his live tour, as talks are continuing about his possible move to Fox. Friedman notes the problem with Conan on Fox is getting affiliates to sign on for a 10:30 p.m. show.

• Milwaukee was the No. 2 market for Olympic viewership on Wednesday night, according to Nielsen numbers, behind Salt Lake City and ahead of Denver. For the first 13 nights of the Vancouver games, Milwaukee is in third place, behind Salt Lake City and Denver, and ahead of Seattle and Minneapolis.
• Speaking of the Olympics, Nielsen put out some stats Thursday about the viewership showing that the primetime audience is 56 percent female, 44 percent male. The Super Bowl audience was 54 percent male, and 46 percent female. Olympic viewing is higher among older viewers than younger ones, according to Nielsen.
• Speaking of Wednesday night's ratings, Fox's "American Idol" beat NBC's Olympics coverage. So far, it's only been beaten once, the previous Wednesday, by the Olympics. Wednesday's "Idol" averaged 22.8 million viewers.
• Speaking of "Idol," Milwaukee's Danny Gokey will sing "My Best Days Are Ahead of Me" on next Thursday's results show, at 7 p.m. on Channel 6.
• Still speaking of "Idol," Ellen DeGeneres' two weeks as a judge on the singing competition is helping her daytime talk show, which airs here at 2 p.m. weekdays on Channel 58. Her weekly national ratings are the best ever, 26 percent higher than the same week last year.
• Don't forget that Sunday is the deadline to nominate a worthy southeast Wisconsin family for ABC's "Extreme Makeover: Home Edition." E-mail your choice to have their home rebuilt to Castingwisconsin@gmail.com.

That "Idol" song: Thursday's quadruple axing on American Idol" marked the unveiling of the show's new au revoir song, Will Young's rather abrupt "Leave Right Now." Young won the first season of "Pop Idol," the British precursor of "Idol"

Here's the video: