Mediated communication, also known as technology-mediated communication, or Computer-mediated communication (CMC)is the transmission of personal or formal information from one person to another through the use of a technology device. It includes emails, text messages, blog posts and responses, status updates, "tweets" (microblogging), and even visual blogging through online or virtual pinboards. All of these conduits send messages written or posted with the purpose to inform, entertain, or persuade the way that traditional writing methods do.
This being said, a good article by professor Derek Lane of the University of Oklahoma (a link to his article is included), explains (from the perspective of 1994) how mediated communication could make or break social interactions. Most of the "cons" of CMC are based on inhibition: do we "switch personalities" when writing online versus speaking face to face? Another "con" is the lack of nonverbal cues. Even with emoticons being available to "back up" our words with "emotions", it is impossible to use an icon that could substitute semantics and intonation when we say things with a specific purpose.
Among the "pros" that he cites are the breaking down of communication barriers, and the convenience and flexibility that come as a result of being able to reach anyone anytime.
Check out also the Journal of Computer-Mediated Communication online (link also provided) which has a number of more recent articles that could help you as well. Enotes also offers a study guide on Communication Theory which can also enhance your research. All resources are included in your answer.