I am not surprised as well
Judging from the poor clock scaling, i believe there is some flaws in their 65nm ramp up (although AMD keeps saying no problem). Besides, there might be due to low yield rate.

Anandtech wrote up something. The poor performance might be due to immature BIOS implementations. My guess wasnt wrong too, the clock scaling is not up to expectation and AMD might delay Barcelona launch.

I guess the performance lost might b due to poor memory utilization by the BIOS (max of DDR2-667 and timing might not b good). It is a miracle if BIOS could make the CPU performance scale exponentially with clock speed LOL.

Maybe it is some pre-fetchers problem, since they are new.
Besides this, maybe the performance is not up to expectations in single thread applications due to small L2 caches and 3 issue core. Intel has an absolute advantage when it comes to cache and prefetching.

it depends. BIOS can control the MSRs in CPU to control some parameters, such as enabling/disabling prefetchers, caching and etc. Besides, it also configures thing like memory timing. As we know, memory can affect greatly in certain high BW demanding apps.