In order to succeed, it has to be adopted by most or whole the target group. That's why usability and design issues have to be studied carefully. The difference between newsgroups and mailing lists is that the former show messages on demand while the latter sends the messages immediately since they become available. May provide features such as routing, development of forms and support for differing roles and privileges. Typical features are to detect when schedules conflict or arrange a meeting that suits for everyone.
Concerns are privacy, completeness and accuracy.
For instance, word processors, where asynchronous support is to show authorship, track changes and allow to make annotations and synchronous support means to allow users watch changes in real-time and provide additional communication channels like videophones and chat. Useful for collaborative graphic design, publishing or engineering applications. Video is useful when visual information is discussed, otherwise it doesn't give any extra benefit from a normal telephone. The most interesting in the text version of chat is that we can track the conversation, and have backward reference to it anytime. Features are the equal participation and the anonymity.