I've not had one since launch, but I've had it a while and I find the 3D effects are nice, not IMAX "wow", but I doubt you'll ever get that feeling on any screen smaller than a few meters. My experience is thus:
Monkey Balls - I'm glad I rented this, because I completed the single player in 90 minutes, the 3D really shines here, but you can't use the 3D if you use the motion controls, which is a shame.
Pilotwings Resort - Only played this for about 2 minutes in a shop, but the island looks awesome in 3D, whether this would wear off after time I don't know, but I can imagine it would.
Nintendogs + cats - This is the only game I own and it works well, the 3D doesn't change the game as such, but I always put it on when I can, it just makes it "nicer", it's hard to explain, but it works.
Face Raiders - This is another game that really has to be played in 2D, but I think makes great use of the under-marketed feature of the motion controls, and it's a fun little game!
AR Games - Now, this is where I think the 3DS shines. Forget the 3D, the AR stuff and motion controls are where the good games are going to be. I know it's been done before, but something like the PS Eye or Kinect is not nearly a immersive or "touchable" as the 3DS, they're like a mirror, where as this is a window and for me, it's just better. I want to see more games like this.
Street Pass (especially the Mii Quest) is a nice little touch, I find myself taking my 3DS out with me even when I know I wont get the chance to play on it just to see if I can catch someone else. I also love the 3D effect in all the menus, it's so subtle, but it looks so nice.
I think he is right, people don't understand the 3DS (and you can't really sell it using 2D adverts), but I can see them longer-term being able to sell it on the other features, which (as you can probably tell) I prefer over the 3D effect.
Don't get me wrong, I love playing 'dogs in 3D, but the other features are much better, and easier to market too.