Vignettes is a new feature added to Google Glass with XE9 update, which out puts the photo taken with the actual view in the Google glass screen. So I have taken some Vignettes which shows the Glass initial view and some pages in the Settings.
The last one is a google hangout call notification.
See for instruction on how to take a Vignette through Glass
To create a Vignette, simply press the camera button and single tap on the photo preview shown soon after it and it will show you the option to create Vignette. That’s it you Vignette will be ready to share.