That sounds like a premium paid feature to me - an option to include a large image, or several images, and some text about your icon in case you want to tell people about it. I can't quite see how 'large version' would work - most of my icons don't _have_ large versions, but I might want to post the image they were taken from or the full text; and I might want to say more (what inspired the icon, etc.) And I wouldn't want to do that for all icons, but for some of them, it could be really neat.