Conversion hurdle race
That would work and it made me think of GoogleWave. One of the things that I like about the wave technology is that people would easily be able to invite new contributors to collaborate on a topic they believe the new particpant care about. It could help us answer the questions about "where/what", "why" and probably "how", as the inviter could give new participants the assistance they want. Imagine the impact of most of our contributors inviting new participants to join the movement.
Right now there is a bit of a cultural bias *against* inviting people to edit articles on topics they care about - in particular, when articles are nominated for deletion, there is a stong stance against inviting "meatpuppets" who care about the topic to join the discussion.
I think technology that helps invite people who know and care about a topic to edit it would be good, but I am concerned it would receive cultural resistance. We also especially want to make sure invited participants understand how to edit articles without introducing bias.