I personally think it would be simple enough to just have one thread. After all this is just a for fun contest. So an additional rule could be that only photo entries are able to be posted in the submission thread. You can comment, discuss, etc... but no quoting people's submissions. That way there will only be one photo of each submission in the thread and every photo in the thread is a submission.
Also; No name, wrong size, no entry. Better luck next time. I've received 2 reminders to add a name to my submission and was very appreciative. However if i didn't get any reminders, i wouldn't have needed the second one.
I'm from the Keep It Simple camp and feel there is no need to reinvent the wheel when it's worked well for so long. The most current contest is an anomaly of sorts. Should there be another contest with as much discussion and examples are needed; who ever feels the need to post an example can start a discussion thread to parallel the submission thread.