I read fairly recently on these forums where someone had cornea damage following an eye peck. One of my chickens went for my eyes the other day. Scary! I tell the kids to not put their faces close.
Yes. A few years ago, a young cockerel got curious when I was close and decided to munch on the interesting, glossy, moving object. I was 13 at the time...had to go to the doctor for it (I'll spare you the details). It was pretty embarrassing to explain how it happened.