The Inquirer reports that AMD is declaring that they have successfully had native quad-core processors tape-out and that the chips are targeted for a Q2 07 release. Known throughout the industry as the "K8L" architecture, these new quad-core CPU's will be compatible with all dual-core DDR2 Opteron motherboards. In stark contrast to AMD's native quad-core approach, Intel's "Kentsfield" architecture basically connects two native dual-core processors on the same package. Time will tell which approach will provide the best overall performance, though we will only have to wait until the end of the year to see how Intel's Quad-Core processors perform.
For server chips, you add a little time to that, but for chips going into existing platforms, you can shave a little off. Add in that the tape out probably happened a while ago, and it is just being released now for PR reasons, and you have a rough timeline for release."