Notice anything funny about Mrs. McCain's right hand(s)? What's that, a Photoshop job gone very wrong?
Not so fast. It's a category of apparent error called a mimicking error, for cases in which actual content looks like an error but isn't. Mimicking errors might include a musician including in synthesized music a noise that sounds like it might be a telephone ringing in the background, but isn't; or a texture in a photograph that looks like film grain but isn't.
In this case, a picture published by the New York Times is being shown around the web as a "Photoshop error" when in fact it's nothing of the kind. It's true that Cindy McCain doesn't have three arms. But the appearance that she does is merely an illusion. Her right arm is linked in Jimmy McCain's, and is holding a microphone. The arm that appears to be hanging by her right side (our left) belongs to an individual standing directly behind her; you can see his pants leg to the right of her hip and thigh. The illusion is exacerbated by the "flattening effect" of a long telephoto lens. The effect might mimic a so-called "Photoshop disaster," but it isn't one.
Mike (Thanks to Christopher Gibbs)
Featured Comment by jcyrai: "Getty Images has another shot by Stan Honda that deconstructs the illusion (image 82665115 on gettyimages.com):"