PowerPC speedup by mid-2001?

IBM announced a new technique for increasing processor speeds up to 30%. The new insulating material is known as "low-k dielectric" and according to John Kelly, general manager of IBM's Microelectronics Division "Along with the move from aluminum to copper to improve chip wiring, we believe this will help IBM maintain a one- to two-year lead over the rest of the industry."

That's great John, but where is this 1-2 year lead? Why are PPC's stalled at 500mhz?

MacNN has some more commentary, as well as the quote from an industry leader: "The PowerPC will scream. You will have really fast Macintosh computers."