Here we go again

[Chutzpar]

Shawn's edit's fixed up the shape, but it's also introduced some other problems with flatness - so don't just copy him outright, k?
Overlapping body parts are a good thing- because there's barely any overlap between bodyparts, and because the legs are now on the same plane, it makes it look more flat.

Also in both your original and in Shawn's edit, because of where the hand is, it's creating a pretty bad tangent, which can also make things look flat; if you have the edges of different things lining up with each other, or if their edges overlap but not much, it makes it difficult to read which is actually closer, and also makes it difficult to "fill in" the hidden shapes, which kind of breaks the viewers suspension of disbelief - you don't think "I am looking at a guy" you think "I am looking at a sprite of a guy".
Shawn's edit's better in that regard though because there's a gap between the shoulder and the torso; what you had initially turned the torso into kind of a continuous lump.

Voila: http://designlesson.blogspot.com/2010/10...llels.html
(This also goes into parallels; I'm not seeing any severe parallels here and it's not like you have to absolutely avoid them, but it's important to know what parallels do, so read that too)

I'm also thinking that you need to keep balance in mind- in your original pose, although the way his leg is bent seems a little unnatural, his weight's not distributed evenly - and that's a good thing. It's rare that you'll ever stand with your weight balanced perfectly between both legs, unless you're making a conscious effort to do so.
Do however pay attention to what he's done to the left (our right) leg - it's further back which makes it look much less stiff than what you originally had, because there's less of a perpendicular line (using more curved shapes also helps this!)

To summarise, because I've wall of texted again:
Pay attention to the shapes Shawn's using; they're smoother with softer curves which makes them look prettier.
Also pay attention to how he's redone the upper arm - it makes the pose infinitely easier to read. If you want to check how easy your pose reads, copy it and colour it in solid black - a good pose should still be fairly obvious even in silhouette.
Disregard how Shawn's changed the far leg, and also avoid putting both the legs on the same plane.

I'd do a redline or something, because I really think it'd be more helpful but HURP NOT A SPRITER, working at a small scale absolutely kills me.