The Most inportant difference is the palette. I use 40 colors instead of 8, a really big difference alowing me more colors gradient, more beautiful icons.

Shade Gradients

Magic Gradients

Shade Vs Magic

If you want to make Shade Icons from MagicWB see chapter Icons.
If you are an adict of Picture to Icon convertion (like me :-) you will get very nice looking picture with grey gradient, and nice looking picture too in full colors. (Try it with PictIcon)