Speaking to Polygon today, Nintendo product marketing manager Bill Trinen said that the stand-alone Wii U GamePad, being released in Japan at half the cost of the full console, won’t be priced or released in North America until there’s content that requires doubling up.
https://kotaku.com/the-wii-us-controllers-are-really-expensive-5942876
Second Wii U GamePad won’t be supported or priced at launch in U.S. [Polygon]