cusman on 15 March 2014
Your Nintendo ID is locked to your hardware. It isn't like your Windows Live Account or PSN Account which you can easily use on a new machine and activate the new machine and download your past digital purchases again.
The 3DS and Wii U are both region locked, so you wont be able to use games bought in Japan on your US based original hardware. But you will be able to use eShop to access new US based games and purchase/download and then use them.
