A Google Maps Help thread reports that at least one satellite image in South Africa has a weird posterization effect to it.

You can see it yourself at 33°55’7.79″S, 25°35’2.40″E, or Port Elizabeth, South Africa. Here is a picture:

This looks like a heavily posterized image to me, but I doubt that was the case. There must have been some type of interference when the image was captured?

Forum discussion at Google Maps Help.