That is the price of partisan journalism. Where a commitment to a candidate or a point of view results in hostility and denial toward contraindicative data you've lost your ability to see the story, much less tell it. That explains part of the open anger we see evidenced toward the Tea Parties - the willingness to disparage the participants as "tea-baggers" and oppose rather than interrogate. The difficulty is not that some in the media are like this, because that's always been the case. The difficulty is that so many are now and all in a similar ideological alignment.
The author seems to agree:
It therefore shouldn’t come as a surprise that the mainstream media and their stable of Beltway pundits missed the boat on the public’s reaction to Obama’s health care offensive. Chatting mostly among themselves, susceptible to (if not anxious to pass on) Democratic talking points, and devoid of many (any?) conservative colleagues willing to challenge their assumptions, they are easily blindsided when reality intervenes.
Meanwhile Fox continues to dominate the ratings and their competitors seem baffled by it. At some point you don't even feel sorry for the strident, ignorant parrots anymore, you just turn them off.
the MSM thought FNC was essentialy current afair OReily and his psuedo populism. Instead Glen Beck is a black swan that has ratings which are throwing the rest into seizure.