I meant to add this earlier:
1) Joshua do you have a cite for the precise way you quoted " By convention sweet and by convention bitter, by convention hot, by convention cold, by convention color; but in reality atoms and void."
I like that version as making a very clear point, but maybe that is someone's interpretation?
2) Also I know one of the first comments here was Don's "I'm not sure I completely disagree with Democritus." We then proceeded to discuss the details of what we think is correct. But we shouldn't skip over the question: "What point do we think Diogenes of Oinoanda was arguing?" Was Diogenes accusing Democritus of tending toward skepticism, and linking it to the disagreement with Aristotle as to the flux being too fast to perceive any details, and therefore being the slope to skepticism? Or does anyone see another possible point? If so, what?
I think one of the best ways to keep ourselves on track in studying Epicurus is for us to be sure we can articulate the point that was being made in the text before we decide if we agree or disagree with it. This is one of those texts that's probably not entirely clear on its face, and we need to be sure we all think it means the same thing.