Kid Icarus Uprising ships with six AR cards. These can be used to summon Kid Icarus characters onto your desk for use in virtual battles, which look something like this:
Here's how you can get more cards, and enjoy a delicious (presumably) snack. Takara Tomy will be releasing Kid Icarus Uprising Choco Snacks. Each box includes one of 20 AR cards.
The snacks will be released on March 12, priced ¥100 per box.
It's unclear at present if this is the only way Nintendo will release additional cards, or if we can expect other tie-ups.