Today, a software update hit the Nintendo 3DS which allows users to use their Nintendo ID. By doing this, you will be able to share your wallet for Nintendo’s eShop across both the Wii U and 3DS stores. Additionally, Miiverse is now available on the 3DS allowing you to chat with others about your favorite titles on Nintendo platforms. Similar to the Wii U, 3DS owners will be able to attach screenshots of compatible games with their messages when posting to Miiverse.
You can find additional information at these links: