I don't see it crossing 1 million.

I'm betting it'll be a hit! I mean, it's a multiplayer-cartoony-shooter-with-single-player. Splatoon will appeal to a wide range of players.

Looks like it could be fun, but it really shouldnt be a full priced retail game. Single play with bots and 4v4 online multiplayer should be 20 bucks at most. So i am going to say less than a million. 400-600k

I really have no idea. Somewhere between 200k and 8 million;)

1mil at the most

I don't see it doing very well, although i don't think it will need much to break even.

It will be profitable especially in Japan, but i don't expect it to sell over 1m.

Not really. I mean, technically in New Leaf (3DS) they did add mini games but they didn't last long for me at all. Of course, this is subjective but to me they added next to nothing to the game. You basically go around town and help the townspeople, go fishing, digging, shopping, and whatnot. In New Leaf, they also added the building feature that allows you to fund town projects.

it can be addicting at times but after a while, it does get very repetitive. 

Yea but that's a hell of a lot more content than a few modes and probably a pretty short "story" mode if there actually is one.

True. On the other hand though, I see people play Call Of Duty & Mario Kart online for months...

Splatoon won't be any different...