lol thanks poppa, well that would certainly defeat the purpose of this excersise. More comments would sure have helped though...

Well, if you're open to any critique, then I'd say here are a couple things to look at: First off, you might wanna smooth the lines out more just so it looks more professionally executed, second, you may want the outline (if you're gonna have an outline at all) to have gradation as the shadows come to light. Example: take a look at the top of that ball there, and make the outline that goes around there, baaaaarely visible/very light color (again, assuming you even want an outline. realism has no outlines.). Third, define a core shadow, the darkest dark area on the object (example: the bottom right region of the ball). Fourth, you want to define the reflective light (the light reflecting off the surface the object is on and back onto the object itself). It's a very thin light color line that goes outside and around the core shadow. Those pointers should help assuming I explained in a way it can be understood.

Here, look at this example:
http://www.anticz.com/drawing1.htm