By lightly used he means way overused in NSMBW, right?

Dude

Wrigglers are in only a few levels in NSMBWii, though the Bullet Bill launchers are plentiful. He might have meant the big bullet, Banzai Bill, which is seen in one or two stages.

3D already enhanced Mario... way back on the Nintendo 64! Word usage is about to get even more confusing...

Do you want the 3D 2D Mario game or the 3D 3D Mario game?

I'm with Mop.  The 3DS has introduced a rather frustrating word confusion.  We've used "3D" to describe polygonal games since the Playstation.  But what other term could be used for this type of 3D?  It's a bummer and there is no obvious way around it.

Reading this I realize that this is going to be an issue for people with depth perception problems.  Fortunately I'm not one of them and realistically colourblind people have simliar issues.  If 3D is just a "for fun" novelty then it's so big deal.  But when you plan to use it in a truly meaningful way then it becomes mandatory and that means a percentage of gamers can't play your game when their vision disability did not affect their gaming experience before.

This worries me a lot, not for those people's sake, but for my own. I'm afraid Nintendo's going to use that as a reason to not take full advantage of the 3D effect for gameplay purposes.

There's a word for this new type of 3D, it's stereoscopic 3D. But that's a big word so I don't expect anyone to use it. I guess they could try abbreviating it to S3D but I still doubt it.

yeah people should stop saying 3d and say stereoscopic..i had to clear that up the other day when I was talking about how I do CG

I was explaining to this person that I do computer graphics, all though I rarely say computer graphics, I usually say 3d graphics, because if you say computer graphics they just think you do graphic design like photoshop or illustrator stuff. If you say 3d to art people, that pretty much means you do sculpting rather than painting. So I said I do 3d graphics, and she's like "everything is in 3d now", i was like yeah. Then I had to explain the difference between 3d CG, and Stereoscopic 3d.
I also never say I do CG, because I live near a town called Casa Grande, which people in passing abbreviate to CG. Not to mention the confusion caused by an anglicized pronunciation (Cassa Grayand instead of Cahsah Granday)