As many of you have probably noticed by now, the Nintendo Network has been down since yesterday for both the 3DS and Wii U. The cause was both the influx of people using their newly received consoles/handhelds from Christmas, and the recent launch of the PokeBank in Japan.
Due to the sudden increase in new users on their servers, Nintendo have decided to remove the app from Japan. Serebii.net are also reporting that the PokeBank, which was supposed to come out tomorrow for the West, has had its release date changed to TBD.
Hopefully we will get more information from Nintendo soon about the release of the service in the West and its return in Japan.