Facial expression is to sign language what inflection in the voice is to spoken language.
Those in the media who are making a big deal about this are displaying their absolute ignorance of ASL.
That’s hardly been my life experience. I lived and worked with the National Theater of the Deaf [NTD] when it was located in Chester, CT and under the direction of David Hays.
I never once [some were 12 hour days] saw that amount of emoting on the street or the stage. http://www.youtube.com/watch?v=SwUsP8ZoQ_8
Your mileage may differ. :)