Here's a model that you knew was coming. Pick up just the code at the store, go home, and download the full game. At least that's what the Nintendo Wii U
will let you do once it's released.
Now, we sort of have that with some of the Xbox Live games where you can buy them at a place like Gamestop. You just scratch off the covering of the code when you get home and enter it in to initiate the download of the game. Nintendo's going to take it a small step forward and offer this on first party games, not just small downloads.
We've seen signs of this coming, but it looks like Nintendo's going to be the first one to really try and drive this by offering full sized downloads purchasable at retail shops. The 3DS will actually be the first one to take advantage of this with New Super Mario Bros. 2.