Not at all. Inflammatory speech has been a constant from all political parties throughout history, and in all nations. We don't regulate inflammatory speech, because that would mean regulating ALL speech. While all evidence has not been released, the shooter seems to be a left leaning nut, and nothing indicates that he was a follower of Palin. If that turns out to be true, shall we, instead, blame Obama for saying that we should bring a gun to the fight?
I think that would be just as ridiculous as what is being said about Palin. Using the deaths to promote a political ideology is in poor taste, no matter which ideology is being promoted. Watch, within the week, the right will be using the deaths to bludgeon the left, and it will still be disgusting.