See virtual reality below, sliding up the "Slope of Enlightenment" between "Autonomous Field Vehicles" and "Gesture Control?" Don't let the analyst firm's term for where VR is at on the Hype Cycle throw you off — it's just Gartner's way of measuring where emerging technologies are in the zeitgeist.
In plain English, that means VR is close to the point where it's widely understood by the general public. But that doesn't necessarily make it a mainstream technology.