Intel shared at the IDF that Nehalem will feature a native design for the dual, quad and octo-core parts.
Intel's first baby will be quad core and dual core will follow. By the end of 2008 Intel will launch its eight core with sixteen tread.
The magic is that both quad and dual cores are native and intel designed that CPU that it can be native dual, quad and octo core. That is exactly what they are doing but one more time, quad core is the first to arrive in 2H 2008.
On the picture on the right you can see the Nehalem, it's the single-die CPU. The chip with the two dies is a Penryn.