Initiate Voice Chat

I am in the early (envisioning) stages of developing an interactive language learning tool and being a C# developer, am thrilled at the idea of using the Live platform. Is it possible to utilize the available add-ins to initiate a voice chat that could deliver audio (preferably webcam video as well). The session would need to continue with synchronized audio and video.

The text chat will be a breeze, but can I initiate the other functions with the add-in

thanks a ton.