Right now, I can't realistically see any title hitting 10M+. SSB is going to lose sales to the 3DS, and Mario Kart would need a large install base, one that I don't see coming. Outside of those two, no other game has a chance.

Mario Kart 8

every nintendo home console and hendheld have a separate mario kart and they don't eat each other's sales. this will be the only smash brothers on wii u as well as the only smash brohers on 3ds. few will buy one version INSTEAD of the other. a wii u only owner will get the wii u version. a 3ds only ower gets the 3ds version. someone who owns both consoles will probably buy a wii u version or both of them.

3 marios games will do it

Your statement about both owners is hard to say.  I could see the majority of both Wii U and 3DS owners in Japan opting for the 3DS version, as well as it limiting its system selling potential there and elsewhere. 

this i think people are underestimating 3ds, if the rumors of the two versions having parity are true then that gives people less incentive to get a WIi u in the first place and the console aint exactly popular hell im a big Smash fan but i can see myself skipping the WIi U version if true or just waiting till the system gets even cheaper

The smartest thing to do about this whole Smash debacle is to release the WiiU version earlier.

Than other games? For example, FIFA 13 sold 14.5M. AC3 sold 12M. CoD usually sells 20M. Very few games sell that much.

Agreed. The SMARTEST thing to do, would have been to not bother with a 3DS version at all. It has and honestly should have remained a home console only franchise for many reasons:

1. The very possibility that the Wii U version, running on HD hardware with 25gb BluRay capacity discs, would have to "miss out" on ANY sort of content, no matter how small or trival, because Sakurai seems to think the two versions should have "parity". If anything, if the 3DS version is to exist, it should absolutely miss out on content that only the Wii U version has. Most rational people would have expected such in the first place, of a smaller, watered down, portable version.

2. The very possibility that the 3DS version existing could eat into the Wii U version's sales at all. For one thing, it's obviously costing Nintendo much more to develop two versions of the game with two seperate set of similar-but-different assets. For another, all the time and resources or extra bodies they've had invested into the 3DS version all should have been working to on just the Wii U title, to ensure it gets finished and released at a reasonable date, because Wii U really needs more "must have" games. Considering the Wii U version obviously costs more to make because HD development costs more, the 3DS version seems extranious, and with the 3DS version existing, it presents the possibility (however small) that Nintendo might lose some money on the Wii U version of the game. That wouldn't be the case, and wouldn't be a worry in anyone's mind, rationally speaking, if there was only the Wii U title, the only money being spent would be on that game, and the only money people would be paying, would be for that version (the only version) of the game. Yes, the 3DS version could sell very well and make Nintendo some $$$$, but that's not the point, and that does nothing to help Wii U.

3. Fighting games on portable consoles are never a great proposition in the first place. Even with the 3DSXL, playing a fighting game, especially one with up to four characters and all the items and stage hazards and madness that is Smash Bros......it is simply NOT ideal to be trying to view and play that all on a tiny screen. A game like Smash Bros. was tailor made to be played on a big screen in your living room, etc.

But yes, even ignoring all that, I agree with you, they would be smart to release the Wii U version several months ahead of the 3DS version. But even then, there are some folks, like a few in these forums, that seem to be okay with playing the lesser portable version of the game, and would simply wait and buy the 3DS version, because they either already own a 3DS, or buying one is cheaper than buying the newer Wii U console. If they really are married to the idea of making a portable Smash Bros., the best thing they possibly could have done, was NOT make it a port of this Wii U title, but instead waiting until after development of this game were finished, and THEN set to work developing a seperate, completely exclusive 3DS SB game.

In spite of ALL of that, however, I still feel strongly that a lot of people such as myself will prefer the Wii U version, or at the very least want both, and that the Wii U version will enjoy strong sales.

I think that the existence of the 3DS version might be an indication of the merging into a hybrid console for next-gen. Isn't it their last major series that doesn't have a handheld equivalent? Apart from the Wii series, but that can't be made handheld. They might just be hedging their bets; if the Wii games for Wii U do well they have a reason to keep the handheld and home consoles completely separate. If not, they have the option to think of ways to merge the two.