Katie Couric's big career move is paying off--for Meredith Vieira and Rosie O'Donnell.

While Vieira and O'Donnell are enjoying healthy ratings in their new TV jobs, Couric is battling the perception that she's not.

The bad buzz on Couric, who dropped anchor on the CBS Evening News on Sept. 5, is fueled by numbers that have trended in only one direction. And that direction would be down.

Since Couric's debut, her newscast has lost one-third of its audience, from an average of 10.2 million curiosity seekers for the week of Sept. 5-9 down to 7 million diehards for the week of Oct. 2-6, per Nielsen Media Research. Additionally, CBS is now running last behind NBC and ABC in the nightly news race.

Fortunately for Couric, last place isn't anything new to the CBS news division. And, in fact, Couric's last place is a more competitive last place than those managed by her predecessors, Dan Rather and Bob Schieffer.

In his last full week in the anchor chair in 2005, Rather's CBS Evening News was nearly 3 million viewers away from second. In a week similar to Couric's latest ratings period last fall, Schieffer's version was in the cellar by nearly 2 million viewers.

By comparison, Couric was but 1 million viewers away from second-place ABC last week.

Unfortunately for Couric, she's not closing the gap as much as viewers, apparently content to watch their fill of enlarged-prostate ads elsewhere, or perhaps succumbing to advanced age, are abandoning the other nightly news shows.

The state of morning TV, meanwhile, looks rosier, and not just because of the influx of O'Donnell.

At NBC's Today, where Vieira assumed the coanchor seat on Sept. 13, its lead over ABC's Good Morning America is widening. In the most recent ratings period, Sept. 25-Oct. 1, Today averaged 5.7 million viewers, up 2 percent over the same time last year, and up 16 percent on GMA.

And at ABC's The View, where O'Donnell began sitting to the left of Elisabeth Hasselbeck on Sept. 5, the talk show just completed its highest-rated September ever, the network said. In terms of viewers, the program averaged 3.1 million of them.

O'Donnell came to The View after Vieira left for Today to fill in for Couric, who jumped to CBS.

So far, the game of musical jobs has left everyone with a chair. So far.

Other ratings tidbits for the prime-time TV week ended Sunday:

• Audience-wise, ABC's Grey's Anatomy (first place, 22.8 million) is 33 percent bigger than last fall.
• Audience-wise, CBS's CSI (second place, 21.5 million) is 20 percent smaller than last fall.
• Why Charlie Sheen gets paid the big bucks: He's the only guy with a sitcom, Two and a Half Men (10th place, 15.8 million), in the Top 10. Or the Top 20.
• ABC's Ugly Betty (18th place, 14.3 million) and CBS' Shark (19th place, 13.7 million) were the two most watched new shows.
• NBC's Heroes (26th place, 13 million) was the highest rated new show among 18-to-49-year-olds.
• CW's Runaway (113th place, 1.9 million) was the least watched anything not on the network formerly known as Pax.
• Just because a show is elderly doesn't mean its dead. NBC's ER (16th place, 14.7 million) wasn't just the most watched show in its time slot, it was a higher-rated series among 18-to-49-year-olds than all but five series, including trendy freshmen picks Heroes and Ugly Betty.
• On the other hand, just because a show is elderly doesn't mean the competition drops everything to help it cross the street. NBC's Law & Order (41st place, 9.6 million) is down 24 percent from last fall, and having its old-man hat handed to it on Fridays by CBS' Numb3rs (30th place, 11.1 million).
• In the battle to see which ABC show could squander more of its super-sized lead-in, Six Degrees (43rd place, 9.1 million) was the Runaway-esque winner, losing 60 percent of Grey's Anatomy's audience. The other contenders: Brothers & Sisters (25th place, 13 million), which saw 38 percent of Desperate Housewives' faithful tune it out; and, The Nine (28th place, 11.9 million), which lost 37 percent of Lost's tribe.
• In a Wednesday showdown, viewers decided that watching nuclear fallout on CBS' Jericho (10.8 million, 31st place) was fun and all, but saying goodbye to Vivica A. Fox on ABC's Dancing with the Stars (17.5 million, seventh place) was just more important.
• NBC's Friday Night Lights (59th place, 7.2 million) is no Sunday Night Football (15th place, 15.1 million).
• ABC's Saturday Night Football (89th place, 3.7 million) is no Monday Night Football (12.9 million viewers for ESPN--the most watched cable show).
• Among notable cable season premieres: Comedy Central's South Park (3.4 million) and Sci Fi's Battlestar Galactica (2.2 million) were both notable for their relatively big audiences.

On the strength of its crime shows, CBS managed another win as the week's most watched network, averaging 12.5 million viewers. On the strength of Grey's Anatomy, ABC notched another win as the week's highest-rated network in the 18-to-49 demo.

ABC ran second in viewers (11.3 million), followed by NBC (9.9 million) and Fox (7.8 million).

To date, Sunday Night Football continues to be a big winner for NBC--no network has added more pairs of eyeballs (up 10 percent) than the Peacock.

The baseball playoffs, meanwhile, aren't doing Fox any favors. The network is now down 2 percent on the season thanks to the usually underwhelming first-round division series games.

Elsewhere, the CW (3.5 million) was distinguished by America's Next Top Model (72nd place, 5.2 million), encouraged by Veronica Mars (93rd place, 3.4 million) and destroyed by its Monday-bound Sunday comedies.

Here's a look at the 10 most watched prime-time shows for the week ended Sunday, according to Nielsen Media Research:

1. Grey's Anatomy, ABC, 22.8 million viewers
2. CSI, CBS, 21.5 million viewers
3. Desperate Housewives, ABC, 21 million viewers
4. Lost, ABC, 18.8 million viewers
5. Dancing with the Stars (Tuesday), ABC, 18.4 million viewers
6. CSI: Miami, CBS, 17.9 million viewers
7. Dancing with the Stars (Wednesday), ABC, 17.5 million viewer
8. NCIS, CBS, 15.9 million viewers
9. Survivor: Cook Islands, CBS, 15.8 million viewers
10. Two and a Half Men, CBS, 15.796 million viewers