Well that hurts ... until SMM2 releases in two weeks ! Or maybe even Yokai Watch 4, who knows ?
Probably not with YW4, as Nintendo also announced a promotion already for the week after it's release, so that will certainly steal some sales even though it's not massive (a 3000 Yen gift card for free when buying a console - so essentially 30$/€ off). In fact, it's possible that sales will drop WoW because of this despite the YW4 release.
On the other hand, SMM2+Promotion the week after means that there will be a big boost in sales then.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454