Version 7.0.0-13U available via wireless Internet connection includes the following improvements:
Added Support for Nintendo Network IDs:
-Users can now create or link a Nintendo Network ID, which is required to use some network services, from within System Settings
-Nintendo eShop has been updated to support Nintendo Network IDs (*1)
For more information regarding Nintendo Network IDs, please visit our Nintendo Network ID introduction page
-Added Support for Miiverse:
-Users can now view and post to Miiverse from Nintendo 3DS family systems
For more information regarding Miiverse, please visit our Miiverse introduction page
-Added a Software Update Notification:
-A notification will now display when software is started and update data is available (*2)
-Removed the limit to system transfers:
-The previous limit of five system transfers per system has been removed
-Changed the start-up method of Nintendo 3DS Camera from the HOME Menu:
-Pressing the L and R Buttons simultaneously will now start the Nintendo 3DS Camera from the HOME Menu
-Improved system stability and usability:
Further improvements to overall system stability and other minor adjustments have been made to enhance the user experience
*1 Credit card information stored on the Nintendo eShop will be deleted after this update is performed or after linking a new Nintendo Network ID
*2 SpotPass must be enabled to use this feature
Source
Nintendo also posted some links of their own:
MiiVerse
Nintendo Network ID