Earlier quoted context omitted.
The 'new' part of Google Glass is likely to be 'being on your face most of the day'.
Sure. But that isn't really a significant development in AR technology. The Oculus Rift certainly won't be worn all the time.
Of course not, but "always on" is not a very useful feature for VR. It's an incredibly useful feature for AR. Oculus Rift is not a good candidate in any way for an AR platform, since camera pass through to VR is not an acceptable replacement for seeing the world with your actual eyes.