Emotion recognition is the next step in human-computer interaction?

Voice recognition algorithms have advanced steadily in the past few years. And with a new Dragon coming out each year, the super-responsive and virtual friends Siri, and now with Google Voice Search, voice recognition is not going away anytime soon. But, even though we may be successful getting the computer to recognize our speech and transcribing it into words, how do we make the computer truly “understand” us?