Marc Ambinder has a more reasonable version of the Millie Vanilli argument:

Palin’s existence in this debate does not (a) lend her voice any credibility and, beyond that, even if you believe that her experience as a state governor does give her at least a modicum of credibility, it does not follow that, because her voice is credible, it ought to be influential. . . .
The media — by which I mean the cable news networks, primarily, will determine whether Palin’s view on health care becomes influential. There are many Republican, conservative health care spokespeople who have earned the right to speak for their party’s principals, and, truth be told, can recite the talking points (complete with Ronald Reagan quote) better than Palin and her writer can. They’re the ones who should be offended if Palin’s op-ed becomes the voice of the opposition tomorrow, because Palin isn’t seen by most Americans as a particularly trenchent analyst of policy. . . .
So here’s a challenge to the media: if you want to do justice to conservative ideas and find some balance in your coverage tomorrow, book serious Republicans with original ideas on your programs. If you don’t, Palin is giving herself a voice at your expense and through little effort of her own.

He adds:

By implying, incidentally, that Palin gets help from a speechwriter, I mean to make an observation. Barack Obama didn’t draft his op-ed, either. But, reading Obama, it’s not a leap to believe that the ideas are truly his. Palin has no chops and no experience talking about health care and isn’t participating in this debate; the content of her op-ed piece isn’t original, and the points are points that Republicans make every day.
This is the reality. Palin has policy credibility problems. Big ones. A few op-eds aren’t going to help her. But if the media treats her as as a legitimate and influential voice today, she won’t need to do the hard work that will result in her learning more about policy and actually becoming conversant in the issues that she, as a potential presidential candidate, will deal with.

Marc is right to say that MSM decision-makers won’t resist giving Palin a platform because a) they hate the ideas, original or not, and believe that associating them with her will discredit them (as indeed they will in some circles); b) they want her to be the Republican nominee in 2012 because they are convinced she will fail; and c) she looks much better in a skirt than Eric Cantor. Beyond that, Marc’s apparent belief that people need to pass some MSM test of “credibility” before their views can be aired — a completely unbiased test, of course! — is exactly the kind of elitism that Palin effectively plays against.