Of the two original variants, the Developer Kit 1 and 2, the Oculus Rift has sold roughly 175,000 since its inception in 2012. The HTC Vive, taking advantage of a somewhat more mature VR market, has managed to come close to that number in the short time it has been out. Early sales numbers from July reported about 100,000 Vive units sold, but recent data suggests that number was either extremely low, or the Vive has sold like hotcakes from then until now. Specifically, the data comes from a single VR game, purported to be on about 20% of HTC Vive units out there, whose sales figures can be extrapolated into an estimate of roughly 140,000 HTC Vive units in the wild.
The game, "Raw Data", is one of the first true triple-A console experiences for VR, and it shows in the budget and the price. The game's price varies on Valve's 'Steam' service, but the average price is currently sitting pretty at about $36. According to the developer, the game is now on 20% of Vives out there. According to an interview with Fast Company, the game has managed to hit the $1 million mark within a month of release, pointing to a huge demand for a premium title in the VR space. More importantly, however, this figure, divided by the average price of the game, yields a figure of about 140,000 HTC Vive units out there, indicating that the fledgling VR console is catching up to its older competition, and showing that the VR market is beginning to reach consumer console levels of adoption.
While the HTC Vive and Oculus Rift are certainly not putting out numbers on par with traditional game consoles at this time, it would seem that the market is there. Capable PCs that can run VR games are getting cheaper and cheaper, especially with the recent release of NVIDIA's GTX 10XX graphics card lineup making the 9XX lineup, the minimum for VR, that much cheaper. As that price continues to fall, we can likely expect to see increasing adoption of full-service, full-price VR headsets. It only makes sense that consumers would think of these as a longer term investment than a game console, since they can be used for the foreseeable future with PCs that have upgradeable parts. While $600 for the PC and $800 for the headset is a steep barrier of entry, consumers who have the extra money seem to be reaching the consensus that they're paying for a more premium experience than a console like the $399 Sony PlayStation VR paired with a $250 PlayStation 4 or a $399 PlayStation 4 Pro would offer. This is the factor that will likely drive the market in the coming months, along with the possibility of cheaper alternatives hitting the market and consumers jumping on sales.