Freeman
Banned
Game sales are definitely front loaded. But at the end of May at Amazon US, Mario Kart was the 5th best selling game of the year. Since then it has continued to sell in great enough numbers to become the #1 selling game. No idea how that translates into console sales though since Amazon apparently refuses to stock Nintendo hardware.
Looking at Amazon rankings now I see MK8 is right above Titanfall in the 2014 chart. I believe MK8 will have a better effect than Titanfall but it doesn't change the WiiU situation.
Everyone already expected that MK, Smash, Mario, Zelda and even Metroid would show up on the WiiU at some point as they did on the GC, that is not enough.
WiiU is simply not competitive without third-party, as 2015 will prove.