Only thing I would say that isn't 'Rah, that's really good' is that Brock could be shifted over to the right (as you look at it) so that all of his fist is on the picture.
Could possibly add a glass cracking effect over his fist as well, as if he is punching through the 2d barrier of the picture, maybe have the shadow of his fist's thumb visible over the text of The Perfect Storm to add that 3d comin' atcha kinda effect.
Maybe he knows I had already done it, wanted to do it his own way and is playing on the 'Perfect Storm' theme more. I'd like to address the 'shifting to the right' issue as well. If I remember correctly, his right hand in the image is cut off and unless you have the skills to recreate the missing part of his hand (which i don't), you're forced to have it hit the edge. I really like this wallpaper though.
Ah yes! I do have constructive criticism, Brock is intense and a 'Perfect Storm' wouldn't be complete without some lightning. What I would have added are drops of water on the sig to make it look like it has a glass covering. ( Not necessary just an idea )