I find faceblindness interesting, in the sense that to me, how I recognize people is normal - but I recognize by voice, hair, clothing, and context. Outside of that context I often have no idea who someone is. But I can recognize people to some extent, sometimes (like I can sometimes recognize actors, like seeing Jonathan Frakes on The Waltons, but I don't recognize others - like seeing Hugh Laurie on Black Adder. Or for that matter, seeing Rowan Atkinson in anything but Black Adder).
Like seeing Ben Browder on Stargate after seeing him on Farscape. I didn't recognize him at all until I saw Claudia Black on the show (who was far more recognizable to me). Or seeing a video with two people I have met personally, and not recognizing them until one of the participants said something that triggered a memory of her saying something else, and then I stopped and asked, "wait, is that her?" and I had to check her hair, glasses and voice. Then, by extension, I realized who the other person likely is, but didn't have full recognition.
It took me three or four months before I could recognize my therapist by anything but her calling my name, and then it was specifically her hair.
I also noticed while watching Battlestar Galactica that there are several actors who play multiple characters: That is, the human Cylons. Some of them looked the same most of the time, but Tricia Helfer's character had a wide range of hair and clothing styles. In one scene, the intangible and invisible to everyone but Baltar Six changes from her usual hair to a darker color, tied back in a pony tail and wearing sweatpants and a sweatshirt, and I didn't realize she was still Tricia Helfer.
I do forget names as well as faces, but it may also be that by forgetting the face I lose the name, and while I know that a person may know me, I can't recognize them.