I at least agree that Pokémon is probably the only thing that could replicate some of World of Warcraft's success in the MMO world. I know pretty much everything after WoW failed miserably, but I think a Pokémon MMO if done correctly could be very successful. Sadly I don't think Game Freak wants to do home-console games. I also don't think it would be the definitive killer-app for WiiU, just a killer-app for WiiU.

Personally I wouldn't dream of buying it though, because I despise MMO's...

I think that the real ace here is that Sony and MS have entire divisions to fall back on, their gaming division is only one part of a larger puzzle, Nintendo does not have that luxury.
As far as single titles go though, you're probably right.