From what little I played, I hated Mario Galaxy. It could not hold my interest and seemed to be following the trend of whatever I hated about NSMB DS that I couldn't put my finger on.
From what I've seen/played of Super Mario 3D Land on 3DS, I'd rather have that than another Galaxy game any day of the week.
I loved SMG, never got around to the second. I did like Super Mario 3D land better--still playijng it actually. Up to special world 7, just need to knock that and special world 8 out (getting the 3 coins in each level before moving) and I'll be done with it finally. Just distracted by console stuff and Animal Crossing currently.
I don't see any comparison between NSMB DS and Galaxy though. Very different look (and not just the 2D/3D thing), type of level design, control (much floatier in NSMB etc.). Galaxy was probably my favorite 3D Mario before the 3DS one. 3DS one I like best as it feels more like the old games, but in 3D--i.e. shorter, linear levels rather than bigger open worlds to explore for stars, fetch quests etc.
For me, Mario is all about the powerups and how they play into the level design and leverage gameplay. Drop the graphics, music, type of platforming, etc. When they hit all of it right, I get a sense of amazement, like there's a magic behind it. Neither game had that as far as I'm concerned and that's what I meant about them being similar, to me.
SMB3/SMW/SM64 have the magic for me. I was hoping that NSMB DS would be in the vein of the last 2 2D platforming games, but the level design was pretty much straight forward, but my main thought looking back on that game is that the only power ups I remember were the Fire Flower, the Big Mushroom, and the Small Mushroom. I didn't think either of the new mushrooms worked well and the Fire Flower has always been pretty standard... I missed the racoon tail, the cape, yoshi, the things like kuribo's shoe or the hammer bros. suit. The magic just wasn't there and it felt like more of the same and it was a chore. Even at the end of every level, I think it was just a Reznor with more dinosaurs. Oh, let's have two of them now. At least the SMW/SMB3 games had the Koopa Kids with various attack patterns and stuff. It just wasn't good.
I wanted to like SMG, hoping it'd be more like SM64 than SMS. I think I got about 3 or 4 stars before I quit SMG... I loathed the bee suit and some of the mechanics I was running into then. It may have gotten better, but it just felt like a chore to me. That and I hated the controls. I do not like waggle. I do not like motion anything. I prefer a standard controller with classic controls. So in the end, I wasn't having fun, there was no challenge or enjoyment, just annoyance.
So to me, both didn't have that magic -- they were just "innovating" for the sake of innovating, and -- IMO, of course -- they missed the mark so it didn't work for me.
SM3DL seems a lot closer to the stuff that made up SM64 to me but with some nice additions... so I'm hopeful I'll like it best of all the 3D mario games, at least since SM64.