Trevin Wax has compiled a helpful piece for Christianity Today in which he sets in parallel the contrasting views of John Piper and N. T. Wright on the topic of justification. There is an HTML version that you can read, or you can download a PDF of the article as it appeared on the pages of Christianity Today.
Following their recent books interacting with each other’s ideas, John Piper and Tom Wright represent the two sides of the discussion. Here are the books in question …
John Piper, The Future of Justification
Tom Wright, Justification: God’s Plan and Paul’s Vision
See also Tom Wright, What Saint Paul Really Said, especially chapter 7