here and on almost all web collaborative platform we have to do with VERY common problems.
Two things that might help which one good friend has pointed me to:
Below I paraphrase remarks from the book The Five Dysfunctions of a Team (http://en.wikipedia.org/wiki/The_Five_Dysfunctions_of_a_Team
This book explores the fundamental causes of organizational politics and team failure. The five primary dysfunctions
(1)Absence of Trust: which stems from people's unwillingness to be vulnerable within the conversation. People who are not genuinely open with one another about their mistakes and weaknesses make it impossible to build a foundation for trust.
(2)Fear of Conflict: Failure to build trust is damaging because it results in fear of conflict. Conversations that lack trust are incapable of engaging in unfiltered passionate debate of ideas. Instead, they resort to veiled discussions and guarded comments.
(3)Lack of Commitment: Fear of conflict ensures a lack of commitment. Without having aired their opinions in the course of passionate and open debate, people rarely, if ever, buy in and commit to decisions or realisations, though they may feign agreement during the conversation.
(4)Avoidance of Accountability: Lack of real commitment ensures an avoidance of accountability. Without committing to decisions or realisations, even the most focused and driven people often hesitate to call their peers on actions and behaviours that seem counter-productive to the good of the conversation.
(5)Inattention to Results: Failure to hold one another accountable ensures inattention to results, which occurs when people put their individual needs (such as ego, opinions, unquestioned beliefs or reputation) above the collective goal of impersonal, detached and rational testing of ideas that may potentially be of great importance to the survival of humanity.
What you are working on is a VERY complex issue. Here is a link to something that may give insights on how to approach it...
Another issue that might be worth contemplating - I am in the process of bring together a team right now and the approach that I am taking is to make it very clear to everyone that there are no leaders and no followers, and everyone is free and equal - I hope that this will help the members of the group "own it" rather than feel that they are just participating in "someone else's group".
This means that I participate as "just another member" and don't try to guide things but only make suggestions just like anyone else can make suggestions. This can lead to a little chaos at times but in the long term I am hoping that people will become self-motivated and the group will build its own dynamic.