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I have a black Sony Vaio made of the same material as the BlackBook and the magic eraser works amazing. Just dab a tiny bit of water on the eraser and scrub away, it even works on the screen. Makes your laptop sparkle
 
Yes-I tried it on a friend's black Macbook a while back. It had never been cleaned since he purchased it a couple of years prior, and had what looked to be scratches and marks all over the surface. After using the Magic Eraser, it looked absolutely brand new-not a single mark or scuff on the entire unit.

I have used it on my Thinkpads with the same results-makes them look brand new.
 
The magic eraser will work fine on it, just make sure you have a microfiber cloth to dry the screen if you use it on the screen.
 
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