Anyone Know the Difference Between the S1200KP and S1200KPR?

I've written quite a bit about the Intel S1200KP motherboard and I've been pretty happy with it overall. The original board I tested actually failed on me but I might have been at fault. I'm planning to replace it now and I noticed that Intel has released the new S1200KPR but I have been unable to find out how it is different from the original S1200KP. Does anyone have that information?

Update: Thanks to the comment to this post, which references this Intel Communities thread, we now know that the purpose of the S1200KPR is to support Ivy Bridge processors. Apparently there are two additional resistors on the S1200KPR that are not on the S1200KP. Although users are still using Ivy Bridge processors with the S1200KP, it is not recommended or supported.