From the Q and A with Barrett at the end he re-iterated that they have the differnet micro-architecture within the core. But the software support will mean it will run on both. We believe that it will be a pure addressing thing. But until Intel release the part later this year we will not be able to establish if its the AMD instruction set which Intel have IP rights on. From what he said we believe this to be the case, meaning it runs the A64 Windows XP version