This debate is divided into 5 categories.

Which had games with the better setting?

Which had games with the better music?

Which had games with better game design (How the game works)?

Which had games with the better combat gameplay?

Which had games with the better story?

Begin!

3d platformers... Mario Galaxy 1/2 > platformers

Trying way too hard to make a lot of threads

I prefer 3D just because I get to explore the world and get a bit of challenge.

Doin' dat Larry Tesler I see.
I don't have any preferences when it comes to 3D VS. 2D.

3d any day.

Depends on the game and my mood.
R&C Crack in Time, Super Mario Galaxy, Rayman Legends, Super Mario 3D world, DKTF, NSMBU, LBP, Oddworld new n tasty, love em all.

R&C Crack in time wins all the categories for me.

Stop ripping of my thread! How the heck would a platformer have combat mechanics anyway?

3d... Mario 64

2D for simplicity most of the time.

3D if I want a more involved experience

Platformers > Every other genre