Josh Marshall latches on to another point about the news media that I have similarly noticed. Very little original, in-depth reporting about a topic is generally done by most media. Those items that receive wide circulation among the major media have to percolate up through various channels, and, unfortunately, not all of them make it.
My most commong (and amusing) point is a correlation I’ve found between Wired magazine and BusinessWeek. Generally, Wired will report on a given topic, which will be followed up by a similar report viewed with a slightly different perspective in BusinessWeek four to eight weeks later. It could so happen that both sources independently had the same idea, but more likely to me is that someone at the BusinessWeek office is a subscriber.