The audio for John Piper's addresses at New Attitude are now online at DG: Discern What Pleases God—Himself, and Discern What Pleases God—Personal Obedience.
The former is Piper's standard "God's Passion for His Glory" talk. The latter addresses, among other things, the role of obedience in relationship to faith and justification. Some of this comes from the fruit of his recent work on justification in seeking to understand and respond to N. T. Wright.
