Though I'm still new to the discussion, I see seven broad characteristics uniting those advocating the "New Perspective on Paul," better labeled either the New Perspective on Judaism or the New Perspectives on Paul.
1. Against a widely accepted reading of Second Temple Judaism as a religion of legalistic works’ righteousness, Second Temple Judaism is understood as fundamentally a religion of grace, inducting one into the people of God solely by God’s merciful election and thereafter providing means of atonement for transgressions.
2. An appreciation for Paul’s burden for unity among Jews and gentiles rather than Jewish exclusivism must be renewed.
3. Misplaced reliance upon Jewish social identity markers are the heart of what Paul sees as problematic with the Judaism by which he is surrounded and to which he responds (especially in Romans and Galatians).
4. The Reformation provided and promulgated an unsatisfactory reading of Paul, mistakenly viewing Paul either in light of existential anguish over a stricken conscience or through the lens of sixteenth-century Roman Catholicism rather than that of true first-century Judaism.
5. Interpreters of Paul must assiduously avoid reading both Paul and ancient Judaism through modern Western society’s over-individualized bias rather than in the strongly corporate categories in which Paul and his fellow-countrymen actually thought.
6. Romans 9-11 is reestablished as integral, if not climactically central, to Romans.
7. Post-Holocaust ethnic sensitivities must be kept in mind when reading Paul, especially in light of some anti-Semitic pre-Holocaust Pauline interpretation.