During today's Nintendo Direct presentation, more information was announced regarding the Nintendo Network and MiiVerse services for the upcoming Wii U.
Each Wii U console will be capable of holding 12 different Nintendo Network user accounts, that will have their own save data etc... But all downloaded Wii U eShop titles will be playable for all users of the console.
Nintendo hope to bring their ID system to other Nintendo consoles in the future, meaning that the Nintendo 3DS will one day be able to take benefit from Nintendo Network.
As far as MiiVerse is concerned, Nintendo have given us some more information regarding the main hub in which all the social interaction will take place. WaraWara Plaza will be the main home menu for the console and will allow many forms of interaction with other players.