I am a fan of succinct theology, so I am always excited to find a good clear explanation of something and pass it on. I am currently finishing Pastor Michael Lawrence’s (Ph.D.) book “Biblical Theology In The Life of the Church”, Lawrence has a very good explanation of what being a missional church looks like.
“Being missional is not the same as being committed to missions, or being missions-minded. Being missional is a way of thinking about the church and how it relates to the world. A missional church understands that the church does not go on mission, or send people out to do missions. Rather, the church is the mission of God into the world, in order to heal the world and reconcile people to God.” (205)
Just for clarity, Lawrence is not arguing that we stop doing “missions”. But, that’s all I am going to give you, so go read the book.
I highly recommend this book. I am currently reviewing it for PLANTD.COM.
DR. MATT CAPPS 
This is a good post. It hints towards the fact that one walks onto the mission field as soon as he or she walks out of the church building.