What CMC DOES do is make use of self-paced tutorials on anything from grammar to research. It uses hardware and software to connect students so that they may share their work with each other and the teacher more easily. It uses programs like Grammatik to give its students grammatical and stylistic feedback on their writing. It uses invention programs to help students flesh out their topics. As a term applied to electronic discussions, it refers to a situation where people say something in the electronic situation they probably wouldn't say in a face to face situation.
Social norms seem to have been broken because of the electronic element.
The second definition seems more prevalent on the newsgroups, where it refers to jumping on someone's case for some reason. In my opinion, this kind of flaming rarely shuts down the conversation unless it degenerates into the first kind of flaming. Lurking Lurkers are subscribers to electronic forums who rarely or never send contributions to the discussions, content to read what others are writing. This refers to text whose units proceed non-sequentially. It is a computer phenomenon, but a good analogy would be footnote markers, which when encountered, invite you to jump out of the sentence you're currently on and to visit the note at the bottom of the page.