We really don't feel the comment section is the best place to hold a "discussion" that is best for the forums, chat or through Site Mail.  Some images get alot of comments as it is and if we allowed multiple comments the pages would make it hard to keep up with. 

I understand some of the pros of it but please understand that for now we feel this way has been working for some time now and would like to leave as is.

I will put it on my list to discuss for future enhancements.