Its 30x stronger than plastic but also very very brittle (the stronger its made the more brittle), so it shatters.
Hmmm guess that means it will resist scratches more though..... I don't think we can win tbh, maybe a metal backed handset or some type of reenforced plastic back with a coating to stop scratches..... I just don't know
I hope by Christmas that a different type of glass is used because if my GF gets one at her upgrade date then its for sure going to end up just like that.