The trend is a good one: To independently fact-check guests after they appear on the Sunday morning talk shows, since hosts don't have all the resources at hand to do that kind of thing, and even if they did, real-time fact-checking would make for clumsy television. (The Media Matters Action Network has been doing it for months now.)
So I think Jake Tapper at ABC News has the right idea for Beltway TV (first floated by NYU's Jay Rosen) by teaming up with Politifact to fact-check ABC's This Week. And this weekend on CNN's Reliable Sources, host Howard Kurtz aired a lengthy segment in which some guests from last week's Sunday shows were fact-checked.
But go watch the CNN segment here, and I think you'll see the obvious problem that may be lurking: Anxious to appear even-handed, Kurtz's CNN report, I thought, went out of its way to slap the hand of two Democrats (Tim Geithner, Bill Clinton) who made borderline trivial statements last week that hardly seemed worthy of critique, while at the same time CNN easily called out blatant falsehoods by three Republican guests last week. (Senator's Mitch McConnell, Scott Brown, John McCain.)
This is going to be the tricky part and the true test in terms of whether Beltway outlets are actually committed to independent fact-checking, or if this is really just the latest installment of the mainstream media's beloved both-sides-do-it meme. As CNN's initial foray showed, the Republican guests really did just make stuff up. Like, out of whole cloth. But for CNN, it appeared to be much more difficult to find Democrats prevaricating. In fact, I don't think CNN ever did find such examples, but CNN made sure to include Democratic 'examples' to be balanced.
Note to Beltway news corps: Sometimes one side lies much more often than the other. Don't be afraid to report that fact. And don't dilute the fact-checking process by automatically adopting a CYA, both-sides-do-it guideline.