For me it'd have to be Zelda, but Xenoblade is starting to give it some competition!

I seem to mirror the other posters thus far ...

Zelda by a wide margin followed by Splatoon, then X (although the reported 300 hours of play is admittedly daunting considering my schedule)

The Legend of Zelda followed by Xenoblade Chronicles X

Its either Zelda or X

Zelda, then Zelda and last Zelda.

i'm going to break with the consensus picks and say yoshi's woolly world. i think that may very well end up being the best 2d platformer of this console cycle (apologies to tropical freeze), and good-feel are just the people to make a proper follow-up to yoshi's island.

The Legend of Zelda takes the top pick for me as the series always seems to please with each title.

its between Zelda and XCX

At the moment it's Xenoblade, but only because I know so little about Zelda.

Zelda, how could it be anything but.
XCX is a distant 2nd, hoping it can keep me entertained the whole way through this time.
And then Splatoon, this game is my hope for the future of Nintendo.
Also Star Fox is getting no love =P Maybe we could get some footage Nintendo, this used to be on of your bigger franchises at one time.