One quick point before this post. I didn't mean in last week's rather involved suggestion that I was proposing a solution assuming Comprehensible Input as the sole method of teaching. Nor am I opposed to it. I have no idea how anything actually gets taught. I'm just a techie who wonders whether there is any software model of the methods teachers actually use. If my proposal sounds like Comprehensible Input, it's because I was focusing exclusively on finding text to be read as a means of simplifying (perhaps oversimplifying) the model.
Traditionally, the four language skills are listening, speaking, reading, and writing. Is communication using technology a new and separate language skill? To some extent, a student engaged in texting, or on-line chat, or posting to a forum is using a specialized form of reading and writing. However, the skills needed to communicate online are not immediately accessible to someone who has mastered the other skills. This is certainly obvious to people of my generation, seeing younger people's abilities in texting.
I haven't yet found anyone suggesting that computer communications are a fifth skill, except for this presentation by Professors Wayne Wenchao He and Dela Jiao, which hints at the idea in its title A New Five-Skilled Approach to Teaching Chinese. Despite the title, the focus is mainly on using word processing software to aid in learning Chinese characters. It appears to treat computer lookup of characters as an extension of writing.
A number of different academic and commercial systems make use of online chat to encourage language learning. LiveMocha and Buusu are two examples of such commercial sites.Many studies have commented how online, networked communications between students or between a student and a native speaker of the language can greatly enhance learning. I've played with LiveMocha a little and learned an important lesson. I'm not even all that good at online conversations in English.