Some of Tony Jones's thoughts on Emergent...
Immanuel Kant (1724-1804) is possibly best known for the "categorical imperative." He believed that there is a transcendent, objective moral/ethical obligation "out there." As human beings, our job is to figure it out, articulate it in contemporary language, and then apply it.
G.W.F. Hegel (1770-1831), on the other hand, believed that moral/ethical norms come become known through a dialectical process of practice and reflection. As a result of this process, a "reflective equilibrium" is achieved.
So, it seems to me that many of the critics of Emergent at Kantian Christians -- they believe that there is a certain, correct, objective interpretation of God's truth as revealed in scripture and the person of Jesus Christ. If they can just get us to stake our claim, then they can see where we are relative to their position, and then they can label us as "conservative," "liberal," "evangelical," "mainline," "Calvinist," "Arminian," or any other well-established category.
Emergent, however, I dare say, is a very loose collection of Christians who are committed to Hegelian dialectical and Aristotelian practical reasoning [thanks, Chris]. That is to say, we want to carve out a place for conversation, dialogue, dialectic, and debate. We also want to place practice at the very center of theology. That is, theology isn't just about getting what we believe right; it's a rich matrix of what we believe and how we live that matters for the Christian faith.