The wizard neck is the flattest, thinnest (front to back) neck I've seen. It is fairly wide (e-string to e-string).
here's an image showing an enlarged cross-section from this page:
http://www.warmoth.com/common/frames/guitarneck.htm
I don't know if Warmoth's wizard is supposed to be just like Ibanez's, but I suspect that's what it's meant to be.