TG Daily says the Nehalem processor will play nicely with high-end memory because the bandwidth will no longer be constrained by the FSB:
However, dual-channel memory can offer a bandwidth that exceeds what FSB can take: 12.8 GB/s (DDR2-800) to 32 GB/s (DDR3-2000). Even if you buy those ultra-expensive DDR3-2000 devices you won’t see a dramatic increase in performance, at least if you don’t overclock the FSB at the same time. To support that 32 GB/s bandwidth, you would need a CPU capable of running a 4 GHz FSB (1000 QDR).
Intel Nehalem architecture uses 64-bit memory controllers that are directly connected within the CPU silicon, eliminating those "FSB brakes". Expect you bandwidth utilization jumps from current 50-60% to 90%.
Industry sources now indicated that the mainstream Nehalem processor code-named Lynnfield will be able to almost double the memory bandwidth – to about 18.5-20.1 GB/s when DDR3-1333 modules are used.
If you own or plan to buy DDR3 memory, prepare yourself mentally and financially for Nehalem. Intel is currently preparing two different desktop parts: Bloomfield will become the new Core Extreme and feature a triple-DDR3 controller. Using three or six DDR3-1333 modules you should be able to achieve 30 GB/s, while Lynnfield will arrive in Q1 2009 and offer a regular dual-channel DDR3-1333 controller.