Matt and the other guys really did most of the technical stuff on the board in the set up and initial operation. That being said my guess is that there is a size limit to each person's picture folder. If Matt doesn't have the answer whenever he gets back on the board I will find out. I doubt it would be the quantity of pictures that would be the limit as much as the size limit in total. (but I am not sure)
edited to add a thanks to Eric for the tip above