galaxy is the only mario that feels next gen. wiiu should have had it. they could have used the hd graphics to do some amazing things.

That and marketing.  Need I remind you the only ad most people saw involving SM3DW was the embarrassing and laughable "Pitch" commercial with the awful child actors.  The Wii and its software, on the other hand, had a lot of promotion from launch through 2008.

Yeah, true that, though I would argue that advertising is part of a game's appeal, as it helps define its image.

Though the poll clearly shows disagreement, I think the correct answer was Super Mario 3D World. My rationale is this.

Galaxy vs New Super Mario Bros Wii = 11 mill vs 28 mill
3D Land vs New Super Mario Bros 2 = 10 mill vs 8.6 mill

Conclusion: 3D Land series picks up sales easier than Galaxy series (when looked at with respect to their individual consoles). Therefore 3D World would have sold better than Galaxy 3.

There are about a million logical pitfalls here but suffice it to say I think 3D World did about as a 3D Mario could hope with the Wii U install base. 3D Mario simply isn't as lucrative a series as the ones that have overtaken it in sales - it could never hope to compete with 2D Mario or Mario Kart anymore.

They have a better game to promote. It was easy to make good marketing with a great game.