2) will the Nintendo Network ID account be restricted to.... LOCATION! That would kill all the importing. Even if you have a Japanese console, you can't use it if you are not IN Japan. Even if you have an American console, you can't use it if you are not in America. I know it's a bit far-fetched, but it is possible, so the moment the new update comes and renders my Japanese and American console void and null... I will throw them at the nearest wall.
This is still Nintendo we are talking about. I don't think they can add something as big as that in a update. I think the only problem you could possibly run into is by connecting EU NNID with a Japanese 3DS. The 3DS NNID won't be used to completely overshadow the FC. It will be only used for E-Shop but friend lists will still require FC. That's probably the reason why Mii verse wont have a "add as friend" button (its already confirmed). Unfortunately it is also confirmed that Mii verse wont gonna have Private messages so another not so useful as hoped feature. Yaay!!