For me, the interesting thing about Ready Player One isn't the VR or treadmills. It's the ability to seamlessly transition between games that seems like the killer app that will come from that.

The vast majority of video games these days are of the genre where you're moving a humanoid character around in a 3d environment. I'd love to see somebody come out with a bridge that allowed you to hop between various types of those games.

You should be able to seamlessly go from playing Tony Hawk Pro Skater to Grand Theft Auto to Skyrim on the fly. The only real differences in those games are the scenery and what details they chose to spend effort refining. One day somebody will figure out how to extract the commonality and convince enough studios to get on board building on top of it as a platform, and you'll get a pretty good first cut of the Oasis.