As Reformission combines the best aspects of each type of Christianity. (The Gospel, The Culture, and The Church) Living in the tension of being culturally liberal yet theologically conservative Christians and churches who are absolutely driven by the gospel of grace to love their Lord, their neghbors, and their fellow Christians. (pp. 15)
Driscoll has three basic presuppositions, one is about culture, the other about the church, and the last is about the gospel. And these assumptions all intertwine. It is the the gospel transforms people, creating the church, thus transforming culture. Driscoll teaches that Gospel Christians will take up the good news and live it out in their lives in a godly way. He is not alone on this presumption - Tim Keller, John Piper, Josh Harris, Mark Dever, DA Carson, and many others preach the same message.
It is a beautiful message to preach and certainly grasps the biblical understanding of how Christians are to reach the world. Driscoll sums it up as... reformission begins with a simple return to Jesus, who, by grace saves us and sends us into reformission. Jesus has called us to the gospel (loving our Lord), the culture (loving our neighbor), and the church (loving our Christian brothers and sisters.)
The Parachurch fails here being a simple formula that sacrifices the church (gospel + culture - church). And Liberalism skews Christ as it burns the gospel (Culture + Church - Gospel). And our fundamentalists say the church and gospel has nothing to do with culture (Gospel + Church - Culture). All in all it sounds a lot like R. Niehbur's Christ and Culture models.
I promised a few days ago a review of Driscoll's book Confessions of Reformission Rev. This is not it, instead it is an overview of Mark's biggest theme which is in another book.