Well, I took the image and scaled it to "standard" 60x60 size and the 3D effect is clearly reduced. So the icons look gorgeous at the size you posted, but smaller icons simply don't offer the same "pop".
Also, this design limits the amount of detail you can give your icons. It lends itself more to larger, less detailed objects. So the AIM symbol is good, but Mario is already problematic... Who am I telling this, you know it.