Here are a couple of new Glass macro images, this time showing the inside of Glass.
The screen is on, but you can’t really tell without looking at the reflection. Look at the reflected (lower) prism and you can see the time of 8:14 shown backwards, small and faint.
Also, if you look to the right of the prism you’ll see the inner camera/light sensor. This is what makes head detection possible. I believe it is also responsible for wink detection, although so far I’ve not been able to confirm that. Here’s a closer look: