Nintendo's portable strategy is undeniably successful in Japan. Pokemon X/Y has been the top-selling game over there for four straight weeks, breaking three million copies sold in the week of October 28. But what about the Wii U, the system that's been an undeniable sales disappointment in the US and Japan so far? If the performance of Wii U Party is any indication, the system may have a stronger holiday showing than expected.

Just under 80,000 copies of Wii U Party were sold in its launch week in Japan. "Wii Party U is the first Wii U title to make it into the top 10 in a while," said Akinori Nakamura, visual studies professor at Ritsumeikan University, in comments printed in Famitsu magazine. "Considering that the Wii U still has a while to go in terms of hardware propagation, selling nearly 80,000 copies in the first is a pretty decent number."

More interesting, however, is the fact that the party game seems to have driven Wii U hardware sales like little else has. Nintendo sold just over 40,000 Wii U systems in Japan in the first week of November, way up from the several thousand or so they were selling per week for all of October.

"Family/party games are always strong holiday sellers, and you can see how this game might be a long-seller," Nakamura said. "Casual games like these have moved over to smartphones and tablets in droves as of late. Wii Party U has taken assorted steps to emphasize the experience of playing in front of a big screen; it's a 'casual' title, but on a design level, it's very different from a smartphone game."

Nintendo may need all the boost that Wii Party U can give it: Super Mario 3D World is the only other major Wii U holiday release yet to come out in Japan.