OCWorkbench has word of new sockets from AMD, called M2 and S1:[Read more]Socket M2 uses the PGA packaging similar to the Socket 939. As some people thought that M2 [would be] over a thousand pins, it is actually 940 pins. The bad thing about it is that it is incompatible with existing socket 940 Opterons.
On the other hand, there is another Socket type known as Socket S1 which is for the mobile processors. Again, the number of pins drops from existing 754 pins to 638 pins.