Fox, as expected, returned to the top of the network heap after "American Idol" brought in some of the best numbers seen so far this season.

A 15.4 rating/23 rating average overnight through the course of four episodes topped anything else seen so far in the 2009-10 season when comparing first-run, non-news and non-event programming. Although Fox also had the lowest-rated show of the week -- a 1.4/2 from "Dollhouse" on Friday -- it was still enough to give Fox the best weekly win yet with a 9.1/14.

The previous best was set by ABC all the way back on Sept. 20 with an 8.8/14.

With "Dollhouse" not even part of this week's schedule, Fox has a chance to hit the 9.5 household rating this coming week, possibly pushing its overall rating into third place. Fox already improved its season average from a 3.8 to a 4.1 household in just a single week, now breathing down the neck of NBC, which is averaging a 4.2/7, but slipping despite the return of "Chuck."

CBS dominated the non-Fox portions of the weekly top 10 with a very strong outing from "NCIS" finishing more than 2 percent above its season average, and a surprising surge from "Two and a Half Men" -- possibly fueled a bit by the domestic violence scandal surrounding its star Charlie Sheen -- posting its best numbers of the season (a 10.2/15), a whopping 17 percent over its season average.

"Big Bang Theory" broke into the top 10 with a 9.3/14, matching its series high set in its most recent airing Dec. 14, and finishing more than 13 percent above its season average.

"CSI" returned to form with a 9.5/15, matching its previous airing on Dec. 17, but finishing slightly below its season average.

The top shows of the season didn't change much, except with the addition of "American Idol" in the top four spots, pushing everything else down.

Tuesday remains the most-watched night of television with a 5.9/9, followed by Wednesday with a 5.5/9. Thursday has a 5.4/9 average, ahead of Sunday and Monday with a 5.2/8, and Friday with a 3.0/6.

Top 10 Network Shows, Week of Jan. 10 -- [Audience Loyalty Index rating]
1. (-) American Idol (Fox) -- 16.8/25 -- [100.0]
2. (-) American Idol (Fox) -- 15.8/24 -- [100.0]
3. (-) American Idol (Fox) -- 15.0/22 -- [100.0]
4. (-) American Idol (Fox) -- 14.0/22 -- [100.0]
5. (1) NCIS (CBS) -- 12.6/19 -- [95.3]
6. (-) Two and a Half Men (CBS) -- 10.2/15 -- [85.3]
7. (2) NCIS: Los Angeles (CBS) -- 9.7/14 -- [91.9]
8. (-) The Mentalist (CBS) -- 9.6/16 -- [91.5]
9. (-) CSI (CBS) -- 9.5/15 -- [90.6]
10. (-) Big Bang Theory (CBS) -- 9.3/14 -- [88.2]

Top Networks, Week of Jan. 10 -- [ALI]
1. (4) Fox -- 9.1/14 -- [54.2]
2. (1) CBS -- 7.7/12 -- [61.1]
3. (2) ABC -- 4.9/8 -- [55.7]
4. (2) NBC -- 3.8/6 -- [73.1]

Top 10 Network Shows, Season
1. (-) American Idol (Fox) -- 16.8/25
2. (-) American Idol (Fox) -- 15.8/24
3. (-) American Idol (Fox) -- 15.0/22
4. (-) American Idol (Fox) -- 14.0/22
5. (1) NCIS (CBS) -- 12.3/19
6. (2) Dancing With the Stars (ABC) -- 11.6/17
7. (3) Dancing With the Stars (ABC) -- 11.1/17
8. (4) NCIS: Los Angeles (CBS) -- 10.2/16
9. (5) Dancing With the Stars (ABC) -- 9.8/16
10. (6) The Mentalist (CBS) -- 9.7/17

Top Networks, Season
1. (1) CBS -- 7.3/12
2. (2) ABC -- 5.6/9
3. (3) NBC -- 4.2/7
4. (4) Fox -- 4.1/6
5. (5) The CW -- 1.7/3

Fast Nationals usually provide a snapshot of what Americans are watching by pulling numbers from the top urban markets that includes both live viewing and same-day timeshifted viewing. A rating point generally represents more than 1.1 million households while the share indicates the percentage of televisions turned on that was tuned to the specific program. These numbers typically shift when final ratings are issued.

Data collected from The Nielsen Co., as distributed by Zap2it. BlipNetwork tracks non-news, non-event programming, and figures for this story reflect airing of new episodes only. For more information on the Audience Loyalty Index, click here.