The WebVR spec has been updated to Version 1.1 Some functions have been deprecated in favor of new ones that support a wider range of hardware. The normative text describes the processing model in more detail and resolves ambiguity in some security sensitive cases. The deprecated functions should be supported for a few releases to ensure sites have a chance to update. This has already been implemented in experimental Chromium builds available at https://webvr.info
The WebIDL changes that are part of WebVR 1.1 are now stable enough to begin implementation. There is still ongoing work on standardizing the security model and details such as how mouse pointer lock will be applied to protect users.
Our WebVR 1.1 implementation is complete and enabled by default, shipping with Firefox 55 to release. Further expansion of the WebVR API will happen with WebVR 2.0, tracked in Bug 1310678.