Positioning on price and marketing. HTC have addressed the pricing issue by bundling the device with premier hardware, by offering credit options, but they haven't dropped the price permanently. Facebook has deep pockets, and HTC is in financial difficulty, so there is that too. Facebook can only throw money at the problem. OpenVR has the advantage of cultivating a different culture.
Different headsets mean that incremental change is possible. The new LG SteamVR headset is a higher resolution than both the Vive and Facebook device.
http://www.pcadvisor.co.uk/new-prod...release-date-uk-price-features-specs-3655938/
1440x1280 for each eye, both of which refresh at a rate of 90Hz. The PPI is 540
The Oculus Rift headset uses an OLED panel for each eye, each having a resolution of 1080×1200 with 461ppi, which I think is the same as the Vive? I'm running out of time to research this, but iirc, the screen specs of rift and vive are identical.
Vive now has a lighter model than it launched with; a different cable; a new "deluxe" head-harness thing with integrated earphones; a cheaper lighthouse is on the cards.
The open nature of the SteamVR ecosystem ensures such innovation. Look at the new tracker pucks for example, and again the innovation with the lighter, cheaper, lighthouses.
You're looking at a difference in marketing strategy here. Long-term, SteamVR will win the majority market share. Whether it's with the Vive, LG or a.n. other. Facebook's closed, privacy invading approach in the face of other competition will see it wither, no matter how buoyant it is just now. That's why the Vive (or the LG) is currently the better purchase. It's VHS v Betamax, and the Facebook VR machine is Betamax. Technically adept, but ultimately losing out to a more popular standard.