It's more correct to say that Reddit (like HN) is a hybrid of anonymity and identity. It can be truly anonymous (you can quickly create a throwaway account) or you can "prove" to the admins that you are who you say you are (like Bill Gates).
That sounds like a definition of "pseudonymous" to me. Particularly since moot has claimed for a while that part of what makes 4chan works is that you can't maintain an identity.
