I'm a little less certain that sexism is the double standard here. Consider the delightful media coverage of Obama in a swimsuit and the tittering admiration from talking heads of both sexes that followed about his "washboard abs." Was the highly popular "Obama Girl" video of last year any less offensive in this regard than Republican pundits celebrating Sarah Palin's "hotness?" And has analysis of Obama's, or any other politician for that matter, been any less surface and dismissive?
Mind you, the case against a sexist double standard is not so open and shut. Traditionally, a women is sexy or smart and combining both is too much of a good thing and threatening, whereas, traditionally, a man can be both handsome and smart. But even this stereotype has eroded over time. Now our cultural ideals are all pretty people all the time, a blandness and attraction to surfaces and shiny objects reflected by the immaculately groomed very pretty talking heads that dominate our political discourse.
We certainly have a host of double standards in the news and in the media these days. We begin with "my party/person is wonderful and yours is out to destroy the country" and move on to "You must give me the benefit of the doubt for whatever dumb-ass or hateful thing I say/I can be as sensitive as I want about what you say." And of course, the most common of all "lets only cover pretty people and talk about surface crap." As Fourth Estate Barbie & Ken would say: "News is hard, lets do commentary!"
I don't doubt sexism is in there as well, but our modern media double standards have truly gone equal opportunity. There is nothing and no one that cannot be trivialized by the 24-hour news cycle.