Currently, the HTC Vive is the only virtual reality headset that's part of Valve's Steam VR push. That's not because it's the only one, but because it's the only one we know about thus far. "You should think of the Vive as the first in the same way there are multiple Steam Machines," Valve president Gabe Newell told me this morning. In other words, Steam VR is an open platform supported by Valve. "We're building tools and hopefully they're valuable to hardware partners who want to do it. In some cases, we'll take the leadership role in shipping stuff. But we're really just building tools for other people to continue. So you'll see more headsets."