Japanese Super Mario 3D Land game is said to be shipped with a new firmware update for the system. This updates makes the portable's friends list a bit more functional, a button will now allow you to join a friend's game in progress. The firmware update also adds a modification to the console's ability to play flashcarts, a notorious game piracy culprit on portable consoles. Like most game-based firmware updates, the cart requires the update before allowing the user to access Super Mario 3D Land.
It's unclear whether the same firmware update will be present on US and EU carts when the game ships in the coming weeks. It seems that the update isn't an early release of the upcoming November one, which brings a variety of features.
Source- Tiny Cartridge