Although I've been feeding ravens in the winter for many years, they're usually quite aloof and fly off when I try to watch or photograph them in my yard. This one is the most curious I've ever seen, and has recently taken to landing on the roof and looking in our kitchen window at us, sometimes for several minutes. I've even been able to open the window and take a picture of him staring at me, most unusual for a wild raven.
They have a well documented ability to recognize human faces and I'm convinced that many of the neighborhood ravens do recognize me, a friendly human who feeds them in the winter. They talk to me in 'raven talk', a fairly complex language, when I'm passing by, and sometimes fly just over my head, coming very close, when I'm out walking the dogs in the morning. They know they get fed when we get back from our walk.