The DK2 includes a brand-spanking-new positional tracking unit. Essentially, it's a custom-made external IR camera, specially designed to work with the new Development Kit.

According to Oculus VR, "it is not possible to substitute an old webcam, nor is it possible to retrofit the tracking to the original Development Kit."

The Oculus Rift DK2 retains its 360° orientation tracking, with no camera needed—just like the first version of the Oculus Rift. But to get the added benefit of positional tracking, you'll need to be in the external IR camera's field of view.

Positional tracking does what it says on the tin: it tracks the position of your head in 3D space, relative to the sensor. When you lean in to examine a virtual object, the environment zooms in to translate your movement, adding another layer of interactivity and realism.