I believe that ecclessiology is our most flexible of doctrines. In other words when it comes to the mission of the church, in making disciples, that the structures we make, the places we do church have to be formed contextually. So missionaries rather than exporting a form of church to new countries, environments, form the churches indigenously, or rather some do once they see the disasters of importing church from previous missional movements.
So for post-modern people connecting to Jesus and forming church communities, what does church look like without forcing them to do church in modern ways, with modern music, modern clothes.
Much of the emerging church movement/conversation within all denominations (and by that I mean the expression of church that is shared around the same question of how do we do church in our emerging culture and context?), is finding expression in so many new forms of church and new ecclessiolgies. If we are going to be missional we have to have flexible ecclessiologies.
But, here is the big but, I have noticed how so many of us when we change our ecclessiology due to being missional, can become instantly dogmatic about our new forms. I have in many conversations, at many events, and reading many blogs and books, been given the dogmatic advice about the correct forms of church for our emerging culture.
Lets not mistake the freedoms we find and the new ways we prefer church, as the new correct and only valid ways of doing church. We need all the old ecclessiologies, and many more new ones. A deep, broad, diverse ecclessiology, not a new and just as exclusive one.