Then Call of Duty Ghosts is light years better than 3D World

I wasn't implying that Sony or MS develop the best in any genre, that would be as subjective as the OP.  But there are tons of developers out there who do just about every one of those genres better than Nintendo, but to be honest most of those genres N doesn't even touch, so unless you live on a diet of kart racers, party games and platformers, I don't know how you could look at N as the best, consistant in quality for the most part but not the best. 

As far as Xenoblade Chronicles, weren't they developed by Monolift Soft, not Nintendo.  I think the OP was stating N makes the best games but this isn't one they made.  They published it but that doesn't mean they had any artistic input, I could be wrong on this particular example, but N has other studios produce games based on their franchises, but while they may be their characters the game is not made by Nintendo, so I wouldn't count it as anything other than a N exclusive.  The credit goes to the developer for making the game.  Same can be said for the DKC brand, with either Retro or Rare making them.  

Also isn't XC part of the Xenosaga series, maybe a spinoff but it's not an exclusive N franchise, at least it wasn't until recently.  

Finally there are many geners I listed and even more if you want to break them down further or include some others I didn't.  And for the most part N doesn't touch most of them, so I fail to see how Nintendo is the best.  They stick with what they know but they haven't branched out in genres much and that limits their appeal to fans that aren't into platformers or kart racers.  

I guess it's how you want to define it, just because Sony or N or MS owns a subsidiary or has a devleoper make exclusives for their systems, doesn't make it their game, so I wouldn't count the DKC brand anymore as made by Nintendo as I would the Last of Us or Jak and Daxter which were made by Naught Dog, though I could be wrong since I don't pay a lot of attention to that side of gaming and if someone smarter than I can correct me if I'm wrong, I'd be happy to be corrected.  

By the way... Friend Collection (Tomodachi collection) is coming to the West ! Yay ! That´s enough to make Nintendo better than the others.  :P