What type of collaboration is needed for mind mapping software?

Alexander Tyagulsky, marketing manager at CS Odessa (the developer of ConceptDraw MINDMAP), is looking for your help. Specifically, he’s looking for feedback on how you’re collaborating using mind maps. He has identified four different scenarios for map sharing and collaboration:

1. Sharing your maps in read-only mode (where your map is published each time you make changes to it, but others viewing it cannot edit it)
2. Real-time team brainstorming (where team members can add ideas, but only one person can edit the map)
3. Embedding your map into a blog, wiki or web page, again with real-time updates but no capability for others to edit it.
4. Simultaneous editing of a single map by multiple people (where all participants can edit the map in real time).

So what’s your opinion? What type of collaboration is really needed for desktop mind mapping software? Please share your ideas with Alex. Thanks!