We had gotten news from industry insiders that the heatsink mounting holes for LGA1155 and LGA1156 will remain the same. What is of interest is of course, whether LGA1155 processors will be backward compatible with LGA1156 mainboards that are flooding the market right now.
Given the different architecture, we are anticipating vastly different pinouts (or landouts) on the new Sandy Bridge-MS CPUs. It is hence of no surprise that our comparison image shows that the two orientation notches have shifted. Don't expect the new LGA1155 mainboards to befriend LGA1156 CPUs.