The chip will feature 731 million transistors and will be available in four and eight core versions.
Looks like Hyper Theading will make a return in Nehalem. Each core will be able to handle two threads which means you can run up to sixteen threads with the eight-core version. Nehalem will also feature an integrated memory controller and will feature a flexible power management system that can turn cores, threads and cache memory on and off.
Source: FUD Zilla.