I'll wait to pass verdict on Galaxy until I play it, but as of now, I'll take a 2D Mario adventure over any of the 3D incarnations.
I got SMG yesterday as a birthday gift and I have to say, it's pretty damn awesome. I played for a good few hours today. Certainly light years better than Sunshine, and dare I say, better than Mario 64.
The controls are actually pretty standard with relatively little "Wii gimmicky" stuff thrown in, and what is, seems to mix really well with the standard stuff. Joe wasn't kidding when he said it's one of the best looking Wii games so far. Graphics are really, really sharp.
The one downfall for me is the game is kind of easy. The toughest part I've encountered so far is where you have to surf on the back of this sting-ray down these rapids that are suspended in mid-air. There are no sides so if you fall off, you die. Think of the Rainbow Road in Mario Kart 64. This part was a welcome challenge, because the 8 or so stars I collected before that were just a breeze to get. Still, the rapids weren't too tough and I nailed it easily after a couple tries.
So far, great game overall, a must-own for anyone with a Wii.