Reggie: For years this community has said: ‘Dammit Reggie, when you launch, you better launch with a Mario game’. So we launch with a Mario game, and they say, ‘So, what’s more?’”
Nintendo PR Manager Kit Ellis at the end of the IGN Comic Con demo video:
"So that's a look at New Super Mario Bros U, coming out for Wii U not too long after launch."
Iwata said in an Iwata asks that it would be a launch title, so I hope this is just a gaffe from an out of the loop NOA rep and that hasn't changed but the words seem pretty clear.