Why is face-to-face communication the "richest" mode of communication, and what are some of the inherent advantages to negotiating in a face-to-face fashion?

When sending or receiving an electronic mail message, what are the components we should consider? How do norms, roles, and status change as a function of interaction via electronic media? What social dynamics come into play when negotiating via technology?

What are the positive and negative implications for electronic negotiation? Does information technology help or hinder the ability of negotiators to "expand the pie" of resources in a negotiation?

What are some strategies for enhancing technology-mediated negotiations?

Please cite sources.