Great news for gamers who will be going online using their brand new and shiny Wii U console is that this service will be free with no subscription charges at all, unless they are trying to connect another device to the network, then some sort of fee will be charged.
According to the Nintendo CEO, Satoru Iwata in a translation on the Andriasang website, he said that;
He does not necessarily reject the idea of a paid service that allows not just Wii U but various other devices to connect to Nintendo Network. However, when considering Nintendo’s users, a paid membership service is not the best approach. By having everyone use the Miiverse together, word of mouth will more easily spread. This will lead to greater hardware and software sales.
Source [Geeky Gadgets]