I wonder why Uncanny Valley is even more pronounced when the character's mouth is open?
Ever wonder why emoticons are pretty much all mouth-based? We're conditioned to watch people's mouths closely for expressions, and it's easier to tell when something's wrong.
As an addendum to the addendum, asian cultures are more focused on the expressions of the eyes ( hence the western :) and the japanese ^^). Those creepy Tanemura-eyes that make up more then half of the face? they are meant to convey lots and lots of emotion.
