3D headphones have been around for a while, the OSSIC ones are by no means the first. Given that we can tell where a sound is coming from, even with our eyes closed, and given that the sound fields (and phases) in the vicinity of the ears is all that is used to inform that sensation, it seems perfectly plausible to claim that these, and other 5.1 headphones, offer more accurate sound location to the listener than standard 2.0 headphones.
One natural objection to 5.1 headphones arises from making the observation that each individual ear only receives a single "channel" of information; so even if the frequency content of a given sound depends on its location (e.g. sounds behind an observer are slightly muffled because the ear are not facing the right way), a single driver (per ear) could be used to simulate any sound from any location.
However, everyone has different ears, so the transfer functions that you need to apply to a sound to locate it in a particular position is a function of both location and the specific user. Thus, it is actually plausible to claim that there are only two main options to achieve a really accurate result:
- Use 5.1 headphones, and allow the real user's ears to apply the transfer function that their brain is expecting
- Use normal (2.0) headphones, but have some sort of calibration step that measures the properties of the ear, and inform the 3D audio software on the computer to apply transforms accordingly
Frankly, the former option seems more practical, even if it's less cool.