I just finished Mark Driscoll's newest, Death by Love. I really enjoyed it.  The book is a series of letters applying different angles on the atonement to needy sinners in his congregation.  In doing this, he still manages to rightfully keep the atonement centered on penal substitution.  One chapter, dealing with his "unlimited-limited atonement" view, was really persuasive to me.  Dr. Bruce Ware shared this view with me in the van ride back to the airport after our recent Theology Weekend.  It turns out that Ware influenced Driscoll highly in the formulation of this chapter.  I hope to read it again soon, but I think I could buy into it, and it doesn't feel that much different from what I have already been explaining to people in Karis.