I disagree. It's not a display. A display could be connected to other inputs and "display" the content of your choosing. This is a wearable computer ala Magic Leap. Another way to look at it is an iPad with a head-mounted screen and battery fanny pack.
The device runs iPad apps (only) and those apps must be customized to use the 3D space or they will run in 2D. Definitely not a display. A walled-garden computer.
Yes. I saw someone on HN mention that it's an iPad or Macbook for your face. It's not a gaming device, and it's not a FaceTime++/shared presence device (at least, not as it's primary use).
It's price come from the missing content/services. As always, Apple let others build ideas, and a few years from now, it will be omly $350. Monthly.