well, in general, the numbers coorespond w/ the order of hte pictures. this can be more or less relevant, depending on the pics. for random pics, who cares, but if you're posting a string of comics, for example, then order DEFINATELY matters
so, if you're too lazy to do it, and it doesn't take away from the pics, don't bother. but it's kinda weird, to see the model fully clothed, fully neked, then halfway, ya know?