I just bought a Fuji W3 3D camera and was searching the forum to see if there was anything on 3D photography here. This is the only thread I could find lol
I'll comment anyway
If the iPhone could do what the W3 can do, the 3D would be a killer feature. The phone would need a stereoscopic display and dual cameras like the HTC Evo 3D. The one camera, two picture method that Sony/Panasonic are using is a half-assed way to implement 3D, plus you can't record video like that. If you've ever seen a crisp 3D photo on a digital display, glasses-free, there's a huge wow factor. Considering how many people upgraded to the iPhone 4 because of the retina display, I can imagine the same thing happening with a 3D screen. And obviously you'd be able to flip it back to 2D if you wanted. 3D screens eat up battery life fast.
You'd also be able to do a lot of cool 2D stuff with dual cameras on a smartphone. For example you'd be able to take two shots of the same scene simultaneously, with a different AF target, exposure, or filter on each camera. I've been messing around with this on the W3 and it's a lot of fun.
Still, I don't think Apple will be doing 3D for at least a few years. I'm pretty sure the future of 3D will be glasses free displays with head-tracking. Apple is pretty good about not jumping on bleeding edge technology prematurely and right now 90% of the 3D viewers out there (TV's, Laptops, etc) need glasses and are expensive as hell.