Are we talking about handhelds and home consoles?
edit: I mean, I'll assume you are given KH3. I think the 3DS will not be the only system with 2m+ sellers. There's a lot of time for other systems to accomplish this too.
edit 2: I don't have any specifics, but I think the PS Vita, Wii U, and PS4 all have a good chance at having a 2m+ seller in Japan given the right circumstances.








