That detailing is wild! Love the suggestion of desolate landscapes in the texture of the face; it's subtle enough not to look contrived but certainly discernable and contributes to the content/concept. Couple things to consider: the transition between lit and shadowed areas on the forehead looks superb, but it might be a little abrupt down 'round the chin. Perhaps you could just add a touch more detailing to interweave those areas. Also, I'm unclear on your choice of background. Perhaps you have a reason for the rings, but I'm not getting it. My own instincts would suggest something gloomier and more organic--perhaps a hint of other, similarly weathered faces or figures--but that's just one idea. It looks really awesome, though. Hope we see more of your stuff soon.
P.S. The "full version" link takes me to the same image posted above.

Fixed ! thanks for the feedback.

First thing I noticed: I don't like the background, it gives the image an unfinished look imo.
The face itself is very detailed, great texturing.
What I like most is the lighting and the angle,

overall: background not my taste,
the face is great!