Sure, there's quite a bit of story, and you do gain levels as your score increases throughout the game, but instead of a big world ready to be explored, you're ushered from Chapter 1-1 to 1-2, 1-3 and then for a boss fight in 1-4. Repeat through 8-4, just like the good ol' NES days. The end of each world gives you a bit more of the story, introduces a new ability or two and maybe even throws in a new playable character - Peach, Bowser and eventually Luigi all become part of your heroic quartet.
Even the Wii Remote gets in on the old school action - it's held sideways, so everything handles like a true '80s Nintendo game. It's a great sensation to run through locales like Hell (aka the "Underwhere") with an uncomfortable rectangle mashed in your palms. Ah, the joys of pre-ergonomics ergonomics.