Reality Checks Busy community practitioners are not the best models for long term online discussion. In reality, this kind of discussion is more readily pursued by academics, hobbyists, retired people - those with more time than busy practitioners. You will need to carefully structure online opportunities that attract participation but that don't expect too much effort on an ongoing basis. Establish clear guidelines from the start. Otherwise assertive individuals can too easily dominate discussion.
Some individuals are genuinely passionate about an issue and tend to get a wee bit longwinded.
Others feel the need to confront them directly online. Once the issue becomes the process itself rather than the topic at hand, other participants get frustrated and drop out of the discussion. The anonymity of the online process can contribute to this problem. Announce-only or broadcast lists are often more successful in the community context than interactive discussion. Despite the strong vision around interactive discussion - that everyone should be both a publisher and consumer of information, not everyone feels comfortable in that role.