Despite the claims of some that the New Perspective is losing steam--and so many substantive critical responses have been made that it is virtually impossible to promulgate the NP as it was 20 years ago (witness the pseudo-retractions in Dunn, New Perspective on Paul, p. 480 fn 45, 46)--monographs and articles continue to be written interacting in varying degrees with Sanders, Dunn, Wright, and others. Here are some only from 2009. Many more from '08 could be cited (Kirk, Dunn, and Southall come to mind).
Bachmann, Michael. Anti-Judaism in Galatians? Exegetical Studies on a Polemical Letter and on Paul's Theology. Grand Rapids: Eerdmans, 2009.
Beale, G. K. "The Overstated 'New' Perspective?" BBR 19 (2009): 85-94.
Campbell, Douglas. The Deliverance of God: An Apocalyptic of Justification in Paul. Grand Rapids: Eerdmans, 2009.
Das, Andrew. "Paul and Works of Obedience in Second Temple Judaism: Romans 4:4-5 as a 'New Perspective' Case Study." CBQ 71 (2009): 795-812.
Elmer, Ian J. Paul, Jerusalem, and the Judaisers: The Galatian Crisis in Its Broadest Historical Context. WUNT 2/258. Tuebingen: Mohr Siebeck, 2009.
Garlington, Don. "'Even We Have Believed': Galatians 2:15-16 Revisited." CTR 7 (2009): 3-28.
Gorman, Michael. Inhabiting the Cruciform God: Kenosis, Justification, and Theosis in Paul's Narrative Soteriology. Grand Rapids: Eerdmans, 2009.
Meyer, Jason. The End of the Law: Mosaic Covenant in Pauline Theology. NAC Studies in Bible and Theology. Nashville: Broadman & Holman, 2009.
Middleton, Paul, Angus Paddison, and Karen Wenell, eds. Paul, Grace, and Freedom: Essays in Honour of John K. Riches. Edinburgh: T&T Clark, 2009.
Rainbow, Paul. "Justification according to Paul's Thessalonian Correspondence." BBR 19 (2009): 249-74.
Visscher, Gerhard. Romans 4 and the New Perspective on Paul: Faith Embraces the Promise. Studies in Biblical Literature 122. New York: Peter Lang, 2009.
Wright, N. T. Justification: God's Plan and Paul's Vision. Downers Grove: InterVarsity, 2009.
Yinger, Kent. "The Continuing Quest for Jewish Legalism." BBR 19 (2009): 375-91.
This is to say nothing of the conference papers, online dialogue, audio lectures, book reviews, and sources in German (and to a lesser degree French) that have been produced this year.