At some point conservatives need to ask themselves about the larger meaning of this kind of conduct—and Andrew Breitbart’s—for their movement. Beyond the ethics of lying and smear one’s opponents, I would think conservatives would worry about the fact that a large portion of conservative media is dedicated to lying to conservatives. They regard their audience as marks to be misled and exploited, not as customers to be served with useful information.
With Sarah Palin, I would suggest it's half deliberate lying and half ignorance. When she says the Constitution is a religious document, she's clearly being stupid. When she claims the president is a socialist, she's lying. Of course she's not the only suspect in this game. The upshot for these people is "the ends justifying the means." They'll do or say anything to undermine their opponents.
The consequence, however, is ultimately a very confused, contradictory and misinformed wingnuttia.