Blazing - I see some people have left some great thoughts on your blog. I think it is important to study the "reasons for decline" document, but then again I see many entries that seem to break the rules. I also believe they don't care for more abstract designs. I had one declined that had no text and no recognizable image within it, but otherwise is fit the same criteria as these. I think the biggest thing to remember is that threadless definitely has a target audience and a goal to sell shirts (and that is good). If something is declined, it is probably less a comment about quality and more about what has the potential to sell to their specific audience. Much like American idol, if Bruce Springsteen auditioned they would tell him his voice was too rough and dismiss him.
About my design