It's common around the volume buttons but to widely various degrees. For me it's more noticeable at the bottom left where the black navigation bar is always lurking, but only when the brightness is cranked realistically.There were a few posts from people who had their top left corner lit up like a spotlight.
You can RMA your device during the 1 year warranty, and Google will cross ship you a new device so you're not without a phone though temporarily charging you for it. People have used this as an opportunity to inspect and compare the new device before returning whichever they choose.
I'd say some are taking advantage of this somewhat trying to get a "perfect" device, but if you're not happy with the phone Google is willing to work with you.