Both of these series have to do with the relationship between God's law and His gospel. New Covenant Theology overemphasizes the discontinuity while Theonomy sees too much continuity. Waldron's assessment provides a balanced and biblical law/gospel understanding.
Additionally, his site now has Waldron's PhD dissertation online (again, in PDF): Faith, Obedience, and Justification: Current Departures from Sola Fide. It is certainly worth keeping up with Waldron and his growing body of work.