Nintendo weren't trying very hard with NSMB Wii. Look at the reuse of DS art and audio assets, compare it to the production values of Galaxy. Based on sales, they should have devoted more resources to the 2D one.
Miyamoto seemed less enthusiastic about the NSMB game in his interviews, except the four player multiplayer aspect (and to be honest that part was perfect).
There was a lot of reuse of designs and concepts from SMB3, SMW and NSMB DS (and I mean beyond the fact it was a sequel). Some setpieces were lifted entirely. The level design was OK, but the generic use of "ice" and "coast" environments and so on was lazy.
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I can guarantee you that the racoon suit will be a situational powerup, like Galaxy 2's powerups, that is used for certain gimmick sections of the level and wears off after. It ought to be like real Mario powerups: you keep it until you get hurt. But flying would break Galaxy-like level design, so instead of rethinking that they'll just limit your use of it to premade segments. No exploration possible.
