I didn't think this would be a competition because I've never particularly enjoyed Sonic in 3D (shocking I know) and Galaxy was one of the better platformers I've played, but I was just not impressed with 3D World's trailer.  The whole catsuit didn't seem worth spotlighting that much and the co-op I couldn't care less for in a 3D Mario.  Sonic looks cool though very sleek and fast from what I saw.

Sonic Lost World.
Both have lazy, low production values, but from what we've seen so far, Sonic is at least trying on the gameplay front.

Getting Both!!!!! But Sonic gets that one extra point in my book!

Sonic, but nothin wrong with Mario.

http://www.youtube.com/watch?v=ZUffbVtIkfg&feature=c4-overview&list=UUWKqPOP9upUdLIWJb1hc9IA

some opinions on 3d world to chew on

some interesting stuff starting at 8:18 but you can watch the whole thing

Game looks very impressive and from what I was told by the Nintendo reps it was running at native 1080p.  I don't know why people think creating a functional 4 player 3D platformer is so easy.  Very creative levels from what I've played so far, and the four player co-op works really well. Most platformers can't even get two right.  People seem to be confusing "not galaxy" with "lazy".  I'd rather have had a Galaxy game too, but what's there is really fun.

why not both? I am definitely getting both!

Mario & Sonic Lost 3D World

For me it wasn't that "not Galaxy" = "lazy", but that the almost 3DS quality visual fidelity seemed lazy. I realize that the importance of the graphics only goes so far, but that, along with the fact that I had a bit of resentment that we weren't getting Galaxy, left me disappointed initially.

However, upon seeing more videos of the gameplay my opinion has changed quite a bit. That's great to hear that it's running at native 1080 res and I'm actually really looking forward to the game now.

Unfortunately the multiplayer aspect is wasted on me personally since I never play Super Mario games that way. :(

OT: Both.

Native 1080p? I'm a bit skeptical considering NSMBU was 720p, I'll wait for confirmation from another source until I'm convinced, this could be a PR slipup, like Black Ops II being anncounced as 1080p on Wii U last year. If it is 1080p/60fps, then it's not so lazy as I thought technically, it's just that the whole level design feels so safe and tame. Plus the music doesn't seem to be orchestrated like Galaxy's.

It just gave me such an uninspired vibe. As a 3D console Mario game I wanted it to wow me like Mario 64 and the Mario Galaxy games did, but instead I was utterly underwhelmed.