Saw Medevenx's (derogatory) signature and just wanted to say that he definitely can "draw" (anyone that can make a mark on something can draw), but perhaps not as well as you'd like. Being able to draw good line art is still being able to "draw well"
by the common persons standards, however it seems that from an artists perspective this suddenly means being near professional at life drawing, perspective and shading. The problem is a matter of perspective, not arrogance...
You shouldn't demean a fledgling artist for what could essentially be misunderstanding. There are a lot of specialist terms and meanings change between regions and through experience. Also do you not think maybe he's not purposely ignoring criticism but rather not understanding how to apply it or get the same effect
himself without using the work of others? Look at edit 4 -> edit 5, he took #4 and tried to apply what Jesse did in his edit, clearly he's trying to improve whilst using his own work. Everybody else's edits are a massive step up from his capabilities and are not really "lessons" at all so much as pointers to how his end piece should end up, Nate's has some good advice but focusses on colour and not how to shade to create depth which is the part he doesn't understand (plus the variations in his image goes no change, slight change, BAM mega change!). I've seen a lot of people around here that put down fledgling artists for not following "simple" advice which to them contain a load of complex theories. It's like bullying a young child for being worse at basketball than you because after them merely watching you throw a perfect hoop they fail even after 25 attempts. You really shouldn't do it.
tl;dr: Some of you artists on here can be really unhelpful even with your great examples and you can be really nasty at times too. Chill out.
To simplify and properly explain what people are telling you squid is that you should focus on learning to draw the world as it
really is instead of how you think it is. You need to train your brain to not think of objects in silhouettes and discrete distinct colours* but in 3d volumes and light (colour theory). You need to constantly be thinking of proportions (between objects AND individual parts of an object compared to each other) and perspective is important, though if you begin by focussing on proportions then perspective should come easier (as basically it's thinking about the scale of proportions in regards to distance). Picking good colours is not really something that is easy to teach, in reality there are no good colour choices and colour combinations are subjectively good or bad, it's all personal taste and should develop along with your style. However big clusters of unnatural colours are generally disliked from pretty much everyone (what I mean is colours not found in nature - pure red/blue/green and such just simply impossible unless coming directly from a light source).
*Which for the non-artist tend to be really garish colours like in a childs paint set... hmm I just had an insight: maybe that's the problem, from the ages of 1->6 or so we paint and draw with this really horrible palette, then usually people stop painting and when we try later on we find ourselves using the same (bad) colour palette!And here's some useful well known tutorial links:
http://androidarts.com/art_tut.htm http://www.itchstudios.com/psg/tuts/process.jpg http://www.pixel.schlet.net/Lastly I think the guys shoulders are fine, perhaps not realistic but it's clearly a design choice, you're not exactly going to complain that his head is wrong because it's rectangular. However I do think the arms are overlapping the body too much (lazy half-edit-> edited left half and made it symmetrical):

I made him look too fat, but the main point here is that I moved the arms up one pixel and out one pixel, I also messed with the outline, banding and hands a little.