My only problem regarding this issue is that I tend to perceive people's personalities through their avatars, rather than through their posts. I.e. if a person has an avatar I think looks stupid, or that I don't like for no apparent reason, I will draw a parallel to the poster. Of course this changes after reading a lot of the person's posts, but I do initially judge posters by their avatars.
Guess I'm just a shallow person.
Ed.- Of course this works both ways so if I like the avatar... I often also like the poster.