The morning show landscape isn't going to fundamentally change this week.

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Not even with Sarah Palin co-hosting "Today" at NBC, her "lamestream media" nemesis, Katie Couric, guest-anchoring ABC's "Good Morning America," and Oprah Winfrey confiding in her best friend, on "CBS This Morning," that she never imagined how hard it would be to launch her OWN network.

This week's slurry of guests and guest hosts -- which one CBS executive calls a "shower of crazy" -- won't have a long-term impact, because that's not how morning show ratings work. Judging from Monday's ratings, the guests haven't even made much of a short-term impact so far: Ratings for the two top morning shows were down.

Also read: Oprah Winfrey: I Didn't Know Starting a Network Would Be So Hard [5]

The week arrives at a crucial time for all three networks' morning lineups. NBC is trying to hold on to Matt Lauer after losing Couric in 2006 and Meredith Vieira last year -- and has flirted with adding Ryan Seacrest to the mix. (Seacrest announced on "Today" Wednesday that he would be joining NBC's Olympics coverage [3].) The network has long held first place in the mornings, despite being the fourth-place network overall.

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CBS, the most watched network overall, has long been a distant third in the ratings. It has slipped since relaunching its morning show this year with Charlie Rose, Gayle King and Erica Hill, and is building a new show.

Also read: Couric Doesn't Help 'GMA' Close Ratings Gap [6]

Only ABC is gaining in morning ratings and viewers. It is in second place in the morning race and third place overall.

A single guest almost never changes a ratings trend. A rare exception may be Hugh Grant, whose appearance on "The Tonight Show" after his prostitution arrest in 1995 helped Jay Leno start a long run of beating David Letterman.

Also read: Palin Joins 'Today' With Joke About Couric Interview [4]

But that kind of magic doesn't happen often. And almost no one expects it early in the day.

Why? Because morning show allegiances change as slowly and groggily as all morning routines. Ever try to take up jogging in the morning? People change their morning shows about as easily as they take up jogging.

The hosts of a morning show do more to set the tone of a show than individual guests -- and tone is especially crucial early in the day. That's why the affable Lauer is so crucial to "Today" and why, fairly or not, CBS has reshuffled its morning team twice since November 2010.

But most viewers won't change their morning routine for a week of Couric. Or a day of Palin or Winfrey. Or because of Meredith Vieira returning to "Today" on the same Monday that "Good Morning America" welcomed not only Couric, but former President Clinton. (Yes: This is a week so packed with guest appearances that Bill Clinton doesn't merit a mention until now.)

Winfrey may have provided a boost to CBS Monday, but it's hard to say. CBS's ratings appeared -- preliminarily -- to be slightly up. No CBS national numbers were available Tuesday, because CBS, unlike its rivals, didn't hungrily order the earliest-possible Nielsen data. Internal CBS numbers and data from specific markets, however, seemed to point to an uptick.

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This season overall, "Today" averages 5.4 million total viewers, down 1 percent from this time last season. "CBS" averages 2.5 million, down 10 percent. "GMA" averages 4.7 million -- up 5 percent.

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"GMA" is growing faster among viewers the 25 to 54, the demo most important to news advertisers. It is up 14 percent, while CBS is flat and "Today" is down 5 percent.

ABC may have secretly hoped that adding Couric -- the former "Today" host and soon-to-be host of her own daytime talk show -- would draw people who used to watch her with Lauer on "Today." You couldn't blame the network for hoping that perhaps those viewers would even stick around after Couric left.

Monday's ratings suggested that the first part of that wish hasn't come true yet. "Today" won, as it usually does, by half a million total viewers. But ABC sounded nonplussed about it Tuesday -- perhaps because "GMA" has been steadily narrowing its ratings gap with "Today." 

"In many ways it was a typical Monday," ABC spokeswoman Julie Townsend told TheWrap. "'Today' winning is kind of a dog-bites-man story."

She added that ABC has "momentum that's been building for months," adding, "we know this is a marathon."

Asked if he believed special guest appearances could juice a morning show's ratings, "CBS This Morning" executive producer Chris Licht offered this general response: "I would say, 'Do not underestimate the sophistication of the audience.'"

Every network asserts that it cares more about a quality news broadcast in the morning then it does about ratings. Licht says he has the words "competitive and relevant" pasted to his desk. If the show can be those two things, he says, ratings will follow.

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In keeping with the not-about-ratings line, the networks say this week's onslaught of special appearances is largely happenstance.

Regular "GMA" anchor Robin Roberts was scheduled to take vacation this week, and in Couric, Townsend said, ABC just "happened to have someone who's exceptionally good at morning television" to take her place.

King, meanwhile, had arranged for best friend Winfrey to appear on "CBS This Morning" a month ago, Licht said.

It's hard to imagine that NBC didn't bring in Couric's replacement, Vieira, and the subject of one of her toughest interviews, Palin, as direct counters to her week on "GMA." But NBC did not respond to an interview request.

If the network loses its place at the top of the morning, it will be because of a continuing trend, not a few bookings.