According to Famitsu, the Vita's revitalization in sales is all thanks to Omega Force and Tecmo Koei's monster hunting game Toukiden, which sold 127,000 copies in its first week. As a result, Vita sales are up to 34,000 units from its previous week of 14,000.
The Wii U's selling at a stale 5,800 units in Japan. Of course, the reasons that the Nintendo console is failing to move units is obvious. Despite it being well over six months since the console launched, the Wii U has failed to court third party developers and must once again rely on Nintendo's stock of first party titles to attract customers. The recent announcements of the Xbox One and PlayStation 4, both leaps and bounds ahead of the Wii U in terms of processing power, are also doing the console no favors.
This means that Nintendo must continue to rely on the 3DS and its sales until it can produce some first party titles (Pikmin 3, anyone?) that will pick sales up anew.