Thanks for your feedback - I really appreciate it. I've gone back to thread and I've asked some specific questions.  The inner lines confuse me a bit since I'm not sure what you're referring to - I've made some changes but I'm not sure that I have addressed your concerns.

I looked at your tutorial and I wanted to ask your opinion on shadows - can your line art on the outside of a piece not be thicker to suggest shadow? Could I remove the line art altogether?

I think that in the wip topic, people thought you would automatically do the things you did now extra to what you posted in the wip topic, and had no opinion about the background. If you posted this with the question: do you think its finished? I am sure people would have replied.

My opinion:
Your image still contains a lot of inner jaggy lines! Read my small tutorial about them: http://img155.imageshack.us/img155/6295/cleangd4.png
If you would fix that, this pixel art would immediately look a lot more like pixel art instead of a quick doodle. The shadow color on his cloths needs to have more contrast with the normal color, maybe you could create a color that is use able for the beard and the eyebrows as well, to save out colors.
I still see some gray and transparent pixels here and there, that makes things really look rushed and unfinished.
If you are going for a transparent image, it is better not to aa the outside. The aa you have now only works on a light background, but on a dark one (like I am viewing it on at the moment) it works the opposite way and makes your lines look even more pixelly.

Thats the most important things now (wow thats quite a list o.O)

I think you should start with the jaggy lines, its the most important point. Your wip topic is still open, and if you post new versions there ill make sure ill reply :)
Lollige

I was hoping for more specific feedback but there aren't any comments on the WIP thread - what do you feel still needs doing

ah man, this looks great, but still not even close to finished! Why not keep it in the wip topic for a while? there is so much still to be done!