Actually, I love it
My MacBook has already discovered gravity, so this nicely camouflages the blemishes - and it also fixes the one problem I have with the MacBook - its colour (I prefer simple black) :-).
It also helps with the bottom heat of the MacBook Pro - if it needs to do some real work it can get quite warm, and this cover makes it lap compatible (if I was so inclined - I prefer to rest it on a table myself).
Bonus feature: with some foil I can kill that glowing Apple on the lid, or use the lit surface to show something else. At last a use for laser printer foils.. IMHO worth it.