Readers of Atrios will have seen this already, but I feel like it's important to give the video as much circulation as possible, so here.
The worst part of what CBS did is in the editing job. Not pointing out that McCain got the facts wrong is bad enough, but not wholly unexpected--after all, since when has the traditional media ever done real fact-checking, especially on the fly? But that kind of editing is, in my opinion, dishonest. As Matthew Yglesias put it,
Sometimes things have to end up on the cutting room floor in television, but it seems to me that if you show video of a question being asked, you ought to cut to the interviewee answering that question not just show some other film. Certainly when you've got a candidate who's made the idea that he's super-knowledgeable about national security policy misstating the basic facts of the issue that seems noteworthy.And if there was time to edit the piece, then there surely was time to point out after the clip that McCain got the timeline wrong.