hey gubar - your model isn't looking too bad, but there are a few areas that are letting this down.

the big one is the corners of the mouth which just don't look realistic coming to a point - that area needs to have some depth - think of the lips as being the inside of your mouth turned outside in, rather than just being a hole. the eyes are suffering from a similar problem. rather than just being an oval, the edge of the lids need to have two distinct - almost s like - shapes. the ear could do with a bit of thickening up too.

Lastly, the waist could really do with a lot of work. regardless of whether this will be seen in the final model, it really helps to get the shape right - at the moment the hips have not been defined and also the distance from the crotch to the top of the hips is looking too short, making it look like his waist is disappearing into his pelvis.

the back is tough - i would focus on finding a decent anatomy plate that shows the shoulder blade and muscles and then concentrate on getting that triangle region and the shape of the trapezius - which lays over the top - blocked in and then you should have something working a bit better.

apologies for the lengthy crit - think i may have mentioned some of these points in your previous thread so sorry if i'm repeating myself.