Karen King just lectured about this last week in her NT course. I don't have much time to get into this right now, but I'll just post a few thoughts.

It really should be called the New Perspectives on Paul. While they have some unifying features, there are significant variants among the different proposals (Sanders, Wright, Gager, etc.).

That said, I'm honestly disappointed that Witherington didn't even touch on the issue that (IMO) is really at the heart of the NPP: that is the issue of audience. The NPP takes Paul at his word of being "an apostle to the Gentiles." Thus, they assume his letters are written to Gentiles alone (since he founded Gentile communities). This hermeneutical key leads to some really interesting readings of Paul's letters that are very valuable IMO. This is how they understand the ridiculous ways Paul both affirms and denegrates the law over and over (Romans anyone?). From the perspective of someone like Gager (whom Witherington doesn't even mention, yet he's currently one of the most prominant voices of NPP), Paul seems to be envisioning a new way to allow Gentiles into Judaism without the requirements of the law....yet those requirements are still in place for Jews.

That said, I think there are still some interpretive issues in NPP material. I find myself leaning far more toward them than the "Old Paul" folks, yet I'm not entirely convinced the NPP people have it entirely right.

The most startling thing about the NPP, is that if they are even close to right...Paul was misinterpreted early and often, and his program was actually rejected in favor of a supersessionist mode of thought that ultimately led to indescribable atrocities.

I'm curious to see what others think on this issue...