One of the documents I have personally found most influential is H. Jenkins “Confronting the Challenges of Participatory Culture”. The meaning of participatory (or Web 2.0, or the ReadWrite web) seems to be slipping away. I still think content creation is a great opportunity in education. The notion of a participatory culture implies we have the opportunity to both consume and create content. At best, we seem to be drifting toward a feeling that we have contributed something when we point at something someone else has created (my basic issue with those who focus on Twitter).
Anyway, my real intent here is to note that many of the resources funded by the MacArthur foundation are available at no cost through Amazon. The “Confronting the challenges .…” resource was already available as a free pdf, but I prefer resources formatted for the Kindle so that highlighting and note taking work easily. So, go to Amazon and search for Henry Jenkins and you would be able to download the Kindle version (for the Kindle or the Kindle app) as well as other MacArthur foundation resources.