With MK, I think if you look, it has gone over time from a beloved franchise, to being a mainstream mega-franchise. Sales on the SNES and N64, and even GBA versions were good, very good in fact. Sales for DD were okay, and I firmly feel were impacted negatively by their needless experimenting with the very nature of the game with the double-car nonsense. But when MKDS and then MKWii came along, I think they just really took off, alongside those consoles. I think the "expanded audience" nature of the DS and Wii turned a lot more people on to the franchise that might never have bothered with it otherwise. And considering the fact that this MK game is the first one since honestly MKDS to look like they were REALLY trying hard to make not just a good, but a GREAT Mario Kart game. The graphics actually look "Next Gen", the tracks look much more epic and involved, the track designs just from what little we've been shown already look a hell of a lot more inspired and creative compared to what we've gotten in pretty much every MK game since MK64. Hopefully the online modes and amount of in game content will be rich, much more than MKWii had. Hopefully they have the REAL "free for all" Battle Mode back, a healthy amount of racers, including a few new ones thrown in (that aren't dumb and pointless such as Dry Bowser or the baby characters). It would be nice if they'd balance out some of the more ridiculous newer power ups they've come up with over the years, or at least offer the option to turn certain ones on or off, ala Smash Bros. Having that level of customization in Mario Kart would be amazing. And if they can tame the cheap nature the bikes had in MKWii, of course.

If they can manage even some of that, it's going to be a great game. It just looks like they are actually trying for once to make an "Ultimate Mario Kart" type of game, versus "Oh, Another Mario Kart" type of effort. I think that alone will help sell many people, "casual" and "core", on the title. But looking at the trend, I don't think it's unreasonable to believe that MK8 could be a big system seller for Wii U, especially if they are smart and do a MK8 bundle next year. I don't expect it to do the 30 million kind of numbers MK Wii did, but I do think it's entirely possible for MK8 to sell at least 10 million copies, lifetime.

As for Smash, it is more of a stretch, sure, but again, if you look at the trend, each Smash game has sold more and more. It is more a "core" type of franchise, but at the same time I think on some level it too has increased it's mainstream visibility with each iteration. Brawl sold nearly 12 million copies by itself. It is definitely possible that the 3DS version could somewhat canabalize the Wii U version's sales, one good reason why it arguably shouldn't exist, but I still think it always has a chance to hit 10 million lifetime, eventually. Who knows?

And as for Zelda? Well sure, Zelda hasn't yet ever sold that much for one game. TP did sell around 8.4 million copies with the two versions combined. But I do think if they made a massive, epic, gorgeous looking HD Zelda, a game that wasn't "just another Zelda game", but something that looked like a "MUST HAVE", and I don't they even need to really change the basic Zelda formula to do that, I think there could always be a chance. But who knows. *shrugs*

I'd happily trade Smash for Pokemon with the handhelds

OT: I would have said Nintendoland, but it will probably struggle now it's no longer being bundled. NSMBU is a chance depending on how long that bundle hangs around.

Than 'other' games maybe, but not more than the games being discussed.  For example, Mario Kart Wii sold 33.84M. NSMB sold 29.12M/26.83M, that's not even mentioning the 'Wii ____' games (because they had bundles). 

Very few games sell that much, but we happen to be talking about the ones that do. 

3D World, Smash, and Kart.  And obviously NSMBU if it keeps getting bundled.

Those Wii games were a one-off. Nintendo won't get those numbers again. Just look at NSMBWiiU.

Doesn't matter, No console or handheld will reach ps2/DS again but it can always be successful !!!

MK(mortal kombat, of course :P)

Of course - it just won't be as big as the games I mention - which also happen to be handicapped because they aren't Japanese.

"not even the Wii had terribly many 10 million sellers"

...I hope that's a joke. The Wii sold more games over 10 million in it's lifetime than both the PS3 and 360. And let's not bring up by how much.

I am the ultimate Wii U fanboy, but sadly i cant see any 10 million sellers....i can see a few 5-7 million sellers though and 25-30 million consoles sold. Nintendo ending the gen with profits, so all is not lost.