The potential of stereoscopic 3D is that it makes the screen look like a window to a holodeck. You can realize this easily in PC games where the dimensionality of the 3D is configurable on the fly, but from watching movies, this is much harder. If you doubt this, watch my Mass Effect 2 video via usb disk, on a 3DTV. I would say we could use a vocabulary for describing different calibers of 3D though -Movie 3D vs. Game 3D, or Conservative 3D vs. realistic 3D, or shallow 3D vs. realistic 3D.
I will say this one more time, because its hard to understand until you've seen it yourself:
In PC games (and console game, using a workaround) 3D makes the game world look as though it is laid out before you and makes the screen look like a window to a holodeck, only limited by resolution and current graphics technology.
I've seen many people say that holograms will usher in true 3D, but how is a hologram going to make a skyscraper look extremely far up like 3D does (PC gaming 3D), or the chasm at the bottom of a cliff look dangerously far down and look like "its really a 1/4 mile down", or a massive chamber in The Lord of the Rings feel massive. I don't see how the holograms can lay the world out in front of you.
The low dimensionality in movies comes from the fact that to make something feel far away, it must make your eyes stare straight on, like they would in real life when viewing a mountain top in the distance. So if you separate the distant imagery by 6.5cm, which is the average interocular distance (distance between the eyes), what happens to the child who sits in the front row with his/her 2.5cm interocular? Thens theres people who get headaches, and the current assumption [apparently] is that less dimensionality equals less headaches , so they are conservative for that reason to. If that wasn't bad enough, then the moives get played at home and the amount of separation shrinks down to nothing because of the shrinking of the image. I hope eventually they start to film movies with multiple cameras to capture slightly different angles, accounting for adults .vs children and theater screen vs. typical home screen, so that the DVD versions and movie meant for adults would have appropriate depth.