I totally forgot to make my way here to rant (briefly) about this game until I saw the GOTY thread over in general...
Picked 3D world up two weeks ago. As someone who was not a Mario fan before, I sure am now. Let me also say I typically hate platformers. This is one of those games I can't imagine anyone not enjoying to some extent.
I love the blend of uber-modern visual coupled with so many elements of the Mario I recall from my youth. From the soundtrack to the characters and level design, everything gels and culminates in an experience on par with the Mario games I played as a kid. The difference here is, this is far more accessible and (especially early on) a great deal less rage-inducing for someone who sucks at platformers, as I most certainly do.
I feel like this should be called Mario Brothers 3 Part 2. LoL