Also, about the Super Stable 3D on IPS and TN:
If you find an XL with an IPS screen, such as a display model in best buy, target, etc, the Super Stable 3D works impressively well. You can tilt the screen laterally to surprisingly large angles and the 3D still works great and the image stays the same. Sure, there are limits; it doesn't work so well in longitudinal directions and you can't do it too fast, but it's impressive.
In the TN screens, the 3D tracking works, but the image still gets messed up. On the O3DS, you may recall that tilting the 3DS causes a shimmering effect, in addition to the 3D losing focus. For the N3DS with TN screens, the 3D remains in focus, but the shimmering effect remains. The shimmering though, is a bit less intense and occurs much more rapidly, which reduces it's effect, yet it's still very noticeable.
It's kind of why I was disappointed in my N3DS. I was hoping it work work like the display XL models I had played with.