its really simple for me about this subject (the orignal subject anyway, we tend to wonder a little bit), i don't expect any comments at all (mostly cause my art sucks but thats besides the point) That way when someone accually does leave one i'm happy, (reguardless of if its just a "great job" comment, or helpful one). i don't leave many comments myself though, cause i'm horid with words and would end up just saying "nice job" a lot.

i try to veiw ever image that is uploaded (and beleive me it takes a long time sometimes) but i only comment if i find something about the image that really apeals to me, or i know a way to help the image look better (rarely happens). thats why i don't comment a lot, which may be the same case for others.