Stephen nails it perfectly: "Groups require unity, networks require diversity. Groups require coherence, networks require autonomy. Groups require privacy or segregation, networks require openness. Groups require focus of voice, networks require interaction. The group I am with right now is very intent on being a group. That doesn't interest me. I have no wish to lose my identity and my freedom, my empowerment. Because a group is subject to this very objection - backlash, groupthink, the works. But a network is not."
I have struggled with this theme in my own writing for the last several years. I like the individuality that a blog affords - my writing, my thoughts, my space. I don't mind collaborating with others...but only if I don't lose my voice and identity in the process. Our education system is based on groups...but it should be based on networks. Groups don't scale, and the urge to focus and move a group forward in one direction results in marginalizing certain voices in order to pursue the "common good". I'm not comfortable with that. A network (as I've been saying with connectivism) imbues individual nodes with personal voices...and finds it's value in aggregating, not overwriting (marginalizing) nodes not in line with the thinking of the majority.
Sticking in one medium will limit the pool of involvement - better to extend across the space and find involvement tactics that involve and incorporate in multiple ways.
... and also emphasises the need to go where people are, rather than simply set up another place:
Funny thing, 100M+ MySpace members, close to 1M SecondLifers and the explosion of social networking sites is a ripe space to grow involvement. I think that the Tories action, while interesting, is again trying to create another space that they control. Better to go where the voters are (like, say, SoFlow or A Small World) and build from within, rather than from the outside. Use the community within and develop the community - and then grow the space for the community to be involved in. Do you need features that are not already available in the sites today? And if they are not there, could you find ways of meeting the needs without software development (like a forum or a mailing list)? Give it some thought and see what can happen.
All of this confirms to me that attempts to promote collaboration can't be either/or in the approach or media. Some people will prefer groups (forums), others will prefer blogs and networks, just as some like text, others audio or video. The challenge is to (of course) be clear on what you are trying to achieve with whom, and then be prepared to use a mix of methods over time. That will often mean going to "their" places - blog, forum, club, event - and inviting people into "your" place - short-term forum, blog aggregator, event. Hmmm.... it used to be so much easier when we knew where places were.