Oh and one last thing: Take a close look at the reference picture. What is he looking at!? Yes, his guitar. That creates a very strong bond between him and his guitar, something very essential to the whole picture. You should really reflect that in your version, making him look down at his guitar.

 Yes, this stronger contrast in reflections is much better now. I'd personally move the cross down a few pixels and pull down the gap in the shirt to expose more of his breast, but again, thats just me ;-)

thanks for advice!
added some changes to final picture

A bit better. Still, I know you want to be faithful to the original but it would be extremely helpful if you chose a different color or at least shade of grey for the legs compared to the shirt. It all blends so much into each other, its kinda boring.

Another option would be to go much more extreme with the lighting & reflection of light on his cloth, just as in the original picture (you can see the reflection has a strong contrast and sharp outline there)

something like that: http://dl.dropbox.com/u/19659584/TonyIommiF4.png ?

It could use a little bit more contrast on the clothing.

Also, the amount of skin that is seen through the shirt is really a vital part of the appearance which is lacking on your interpretation - so are those leather bands hanging down from the arms. I'd really add those.