I believe that, like NSMBU, 3D World on Wii U will fail to live up to series sales standards, because:
-The "core" will see it as lazy and rehashed due to its modest audiovisual presentation and conservative style compared to the Galaxy games.
- The "casuals" won't see the a significant difference between it and NSMBU and 3D Land.
- Both will be put off by Mario fatigue, with this being the 4th Mario platformer in 2 years.
Nintendo is killing its biggest mascot with these safe, unadventurous, and lately over-abundant entries.
I predict 3D World will land beteen 4m and 5m lifetime sales. For comparison, the current lowest, Mario Sunshine, sold 6.3m, Mario Galaxy is approaching 11m, Galaxy 2 is at 7m, and Mario 64 sold 11.9m.