One other point, a very important one, about the "out of context" question:

"Source amnesia" is a very common and powerful phenomenon, where people's beliefs and emotional connections are concerned.   You may initially temper your reaction to a media report (tabloid?) or bit of gossip or a photograph or cartoon because you discredited the source or the story wasn't substantiated by evidence or even because an image was put forth as a joke, but what tends to linger over time is the allegation or image itself, not where it came from or why.   

Even the 5% in the MediaMatters survey who said "Hilarious. It's perfect satire," the 1% who responded "It's obvious the New Yorker wants Obama to win," the 6% who said "The image will only add to the massive publicity Obama receives while McCain remains in the shadows," and the 7% who agreed that "It will do what it's designed to do: sell magazines" are likely to retain the images in that cartoon long after they've forgotten the article it was supposed to illustrate (if they read it) or even where they got that image.   

Imagine the lingering impact the images may have on those who said they think there's "some truth" in the satirical images or that "the image isn't too far from the dangerous truth about the Obama family."

Research shows that most people are far more likely to base their votes on emotional associations and feelings than on rational consideration of issues and candidates' policies.
I don't see how this can be anything but harmful to Obama and to the Democratic Party in this election cycle.

As Jack The Sailor said,
"In context of their previous style of cartoon, it is a stretch, I think to say that even an avid New Yorker reader would be expected to see the cover in question as anything but mocking the Obamas. Of course the New Yorker has a perfect right to mock the Obamas. My only concern is that they are saying that they are not doing so."