It's fake.
Look at the comparison image of all three systems (MacBook, MacBook Mini, MacBook Air) below.
http://9to5mac.com/files/image/00000/attachment-3.jpg
View full size images, 100% zoom.
Look at the "S" key on the MacBook.
Notice how there is an angled manufacturing distortion (a compression, or crease or stain) running from approximately the centre lower area of the key up towards the right upper corner of the key. This is a result of stresses during the moulding of the plastic keys and is unique.
Now look at the MacBook Mini. Although the key has been lightened in colour, the "S" key shows the exact same deformation as the MacBook. This is also the case with other keys (The 'H' key has three horisontal deformations).
This clearly proves that the keyboard on the "Mini" has been photoshopped from the screenshot of the MacBook.
Thank you Ladies and Gentlemen. Case Closed
