I strongly suggest against anyone "working" for MMOCCs. 99% of them are crap and I've seen multiple sites being run by the same people in order to get free art from people. Chances are you can tell how professional a potential employer is by their use of proper grammar and willingness to set up a contract

Pixel World: http://www.amazon.ca/Pixel-World-Francis-Lam/dp/9889706539/ref=sr_1_2/702-0366202-3358422?ie=UTF8&s=books&qid=1179902350&sr=1-2
Eboy: http://www.amazon.ca/Eboy-Steffen-Sauerteig/dp/1856693031/ref=pd_bbs_sr_1/702-0366202-3358422?ie=UTF8&s=books&qid=1179902420&sr=8-1

that's a bit drastic dude. I think you've just ignored some people's advice altogether... a bit grainy, repetitive, etc.
I really think that there's nothing dynamic about this mockup. Everything very plain and there's not very much contrast. Wroking with sprites that small doesn't leave much room for character either, but I think you could pull it off given the motivation.
How about some baddies or powerups? How about some variation in the tiles? Something different than trees and rocks to add?
There's so much going on in that dirt that the sprite gets lost, IMO.
I hope that's enough critique for you to carry on now. Cheers!

Because I leave so many things unfinished and because it's all the rage these days...

1. The old man. Started as a squiggly line challenge. Sometimes I find it jumpstarts my creativity to just draw some random lines and try to create an image from it. Thus his huge honkin nose. Scanned him in - you can find the original here: http://i2.photobucket.com/albums/y28/pixelblink/oldmansketch.jpg
finished>>
I'm pretty satisfied with this one. Not much changed and I liked the gray on him

2. That damned sneaky pose. Yup.. haven't worked on him for a while but I do plan to finish it. I already understand that the legs are completely unnatural in that stance.


3. I suck. This was for TakaM for the secret santa thingy. My monitor was dying at the time and the colours/contrast seem way off now that I look at it. My major problem that was holding me back was the aliens body. As much as I googled, I couldn't find what I needed.


4. The Gurge sprite. Trying to get a proper body for him. Was planning to animate as well. Alot to improve on I know.


5. Floating Orb-Bot. Drew this awhile back on paper and scanned it in. Cleaned up the lines but it sucks compared to the original drawing (which is MIA somewhere).


6. Old Man Jalonso. For the latest PJ challenge. It's kinda choppy and I'm new to this style of animation. I may work on it some more to make him more fluid.