It's said that this new "magical" B0 stepping increases the clockspeeds by up to 470MHz, without increasing the power consumption at all.
Sources close to the company described the K10 B0 stepping as being able to hit the 45 nanometre speeds with the old 65 nanometre process. At press time there are no launch changes but with the new stepping AMD should be able to reach 3GHz on the quad core or even more for the dual core.The first of these processors are expected by the end of this quarter.
Intel should be worried, but not yet as AMD has still to launch these babies in volume.