I am one of the organizers of the „New Parameterizations for Emotional Speech Synthesis“ group at the 2011 Johns Hopkins CLSP summer workshop.

From the website at http://www.clsp.jhu.edu/workshops/ws11/groups/npess/:

This project's goal is to improve the quality of speech synthesis for spoken dialog systems and speech-to-speech translation systems. Instead of just producing natural sounding high quality speech output from raw text, we will investigate how to make the output speech be stylistically appropriate for the text. For example speech output for the sentence "There is an emergency, please leave the building, now" requires a different style of delivery from a sentences like "Are you hurt?". We will use both speech recorded from actors, and natural examples of emotional speech. Using new articulatory feature extraction techniques, and novel machine learning techniques we will build emotional speech synthesis voices and test them with both objective and subjective measures. This will also require developing new techniques for evaluating our results using crowd-sourcing in an efficient way.