JollyBlogger has a very insightful essay on the question of reform movements in the church, and the Emergent Church's reform movement in particular. He considers a very helpful distinction between "going farther up and further in" to understand and experience Christianity more deeply, and movements that encourage a change of direction.
"'Always reforming' can apply to those bedrock issues in the sense that we have yet to plumb the depths of any of those things. The last word has yet to be said about Scripture, about grace, about faith, about Christ, or about anything in Scripture. Neither the early church, nor the reformers nor their heirs have exhausted the knowledge that is available in any of those areas. And of course, when it comes to the area of Christian practice no one has even come close to exhausted the application of any of those truths to life.
"We can and should affirm the great confessional statements on these matters, but we must realize that they haven't said all there is to be said. One of the characters in the Chronicles of Narnia (I think it was Reepicheep but I'm not sure) spoke of going to Aslan's land with the phrase 'farther up and farther in.' That's a good way of looking at the principle being always reforming.
"There is another problem with this that is twofold and that shows itself in some modern attempts at reformation and some criticisms of modern attempts at reformation. Sometimes modern reformers aren't going further up and further in, they say we were going the wrong direction and want to go a different way altogether. That could be true, but such a notion ought to be looked at with the greatest suspicion."
He goes on to consider whether the bias should be with tradition and suspicion toward the new, or whether the bias is for change and against tradition. This might be one of the fundamental rubs between confessional Christians and the EC.