In reply to Alan James - UKC:
Ok, I'll be a pedant.
There IS an indirect benefit (which could well turn into financial benefit) of more posting about the comp and therefore giving sponsors more exposure. Your a busness, it seems right that you would want this. I just think that the comp could still have great exposure without publishing the entries before the closing date.
I am not saying that the posting of entries will effect the vote a pic gets if the posting of entries before the comp ends does NOT effect what pictures get entered later. The thing is it could (I expect that it is more than likely).
Here is a senario that could happen to help illustrate the issue.
Photographer A has a wonderful inovative idea, takes an ok picture and submits it.
Photographer B sees the idea, takes a photo using the idea which is better technically than photographer As submission.
Under the way you are running the comp at the moment, Photographer B is more likely to win than A(same idea, executed better).
Where as if photos were only published after the closing date, more likely A would have a chance to win with their inovative idea.
I am definately not against you running the comp, think it's a wonderful idea. I just think the way it has been executed could do with a bit of fine tuneing.