This would pawn the FX-55. In every way imaginable ..
I skimmed through that quickly, and I think I caught that it uses an Opteron. The FX-55 will still be faster than even the most powerful Opteron in certain enviroments.
I think a 2.6GHz AMD would match a 4000+, you have to remember the 4000+ uses a larger L2 cache so even if the clock speed was a couple megahertz faster, the cache would compensate up to a certain point.
The Venice cores are coming out on Monday as mentioned above, they do use the same 90nm process of the Winchester but the strained silicon allows AMD to use cores with higher clock speeds now. I have noticed that the Venice maxes out around 2.8GHz, but that could just be because of the chip.