It's for two channel headphone listening. It's very clever and it really works. Also check out 8D audio, which you can find on YouTube amongst others. I am not sure if these are the exact same thing labelled differently or competing technologies, but they both pull off the same trick. A lot of the content which is currently available uses it in a rather gimmicky way, such as having a drummer circle around you, but if producers can learn to exercise some restraint it will be very interesting.