So, you can see it on the photo - a circle with a pale dot in the center.
I wouldn't say it bothers me a lot, but that's really strange - I only have the phone for 2 weeks, never dropped or stored with anything in a pocket, and it doesn't look like a scratch.
It also becomes less visible if I clean it with a microfiber cloth, but comes back as soon as you slide a finger across it.
Any ideas?