The "content" is the full game's data ?
I noticed that the content size is a lot smaller than the ISO's size available on certain websites.
once the wud is extracted it's smaller? there's probably some scrubbing involved?
Captain Toad : 1GB content data, 7GB ISO
Sonic Lost world : 6GB content, 20GB ISO
Mario 3DS world : 1.5GB content, 4GB ISO
maybe games will start to be released in extracted format if the size difference is that big. they won't be clean dump, but releases always adapt to current loading method (see PS3 with extracted game format which superseded full bluray ISO dump because the loader worked with extracted files).