yes but the 8600 doesn't come in AGP!
No one is mentioning the fact that the 2600 is available in AGP and the 8600 is not. I dont use AGP but if you go to Valves system information page you will see that close to 40% of all the people using Valve still use a video card plugged into an AGP slot.
The fact that the 2600 comes in AGP is a HUGE advantage that Nvidia is simply overlooking.