I think the browser will be powerful enough for some simple VR experiences that consumers will want to engage with for <5mins. At least at the beginning. I've been working with the webVR stuff and have gotten a consistent 75 fps on an MBP, which is the DK2 limit. Not a 5 year old laptop, but also not a heavy gaming rig that Oculus expects people to own.

Maybe webVR won't be the way to get AAA titles in VR, but it will certainly lower the barrier to 1) development of VR content 2) distribution. I think webVR can do a lot for the adoption of VR without "poisoning the VR well."