Mine's two blocks tall, all my downloaded GBA/GBC/GB games in one folder, other VC games in another folder
apps in their own folder
all 3ds DL games are on the main part.
Mine's 3 blocks tall, the top row starts with the slot for physical games and then goes to my most played downloaded (eg. New Leaf, Pokemon Y, soon to be Pokemon Omega Ruby). The second row is empty, it contains my other digital downloads until I delete them (I've deleted all of mine that I no longer play). The third has the Mii creator (forget what it's called), photos, music, etc. I have a folder down to the right a ways so you can't see it with the pre-installed applications.