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Defientally looks photoshopped to me, look at the top left corner, looks like it was cut out (probably from a MBP 15"), and fit to the macbook's current dimensions.
 
shadows

Look at the shadows on the left. They are all screwed up. Even if there would be shadows on that side of the laptop, they would be shorter over the cables as they entered the laptop than on the desk. The shadows here are the same length even on the cables/ports. This image is obviously doctored. In face the shadows are the whole edge are messed up, and not congruent with the light source.
 
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