Some sort of newfangled Blu-Ray thing, with sturdy plastic glasses. Still, I've had a thing for 3-D movies since Captain Eo as a kid. Kitschy novelty, but still neat, right?
This hasn't been used by a lot of musicians. In the entire world, at this point in time, the only artists who have done this kind of 3D concert filming are Michael Jackson, U2, Yumi Matsutoya aka Yuming, and Chemical Pictures.
At this point the company is using it sort of as a tech demo...the technology has practical uses but they wanted to show us off too to give an idea of entertainment options that aren't movies.
...and such and so forth