Michael Frost and Alan Hirsch, authors of The Shaping of Things to Come (I'm through some of it, good stuff) and leaders of a missional training organization in Australia called Forge, have come out with a paper (delinked, see updates below) responding to D.A. Carson's Becoming Conversant with the Emerging Church.
I think this is a very helpful document. It makes clear some lines between ec/Emergent stuff and missional. I think I will have more to say about this at a later time.
(HT: Andrew Jones- TSK and Andrew Hamilton, also read the comments on both as Tony Jones, National Coordinator of Emergent chimes in with an unfavorable reading)
UPDATE 7.21.05: Darryl over at Dash House indexes thoughts from Jordon Cooper, Alan Hirsch, and Tony Jones.
UPDATE 7.22.05: Andrew Hamilton has delinked the article and requested others do so while Forge rethinks what was said. Curious. My link is no longer available at this request.