The core2 architecture...

is a descendant of the original pentium pro line, like the PII and the PIII. The changes are the following: implementation of the x86-64 instruction set and paging mechanism, addition of the 32 and the 64 bit virtual mode support and one more pipeline. (the ppro had 2 alus, the core2 has 3 which is the same as in amd athlons) Fortunately they left the rest of the architecture as it was in the original design. Currently the core2 and amd athlon architecture looks almost the same except that amd doesn't have the technology to reach higher clockspeeds. One possible exension of this technology in the future is to add one more pipeline making a ppro architecture cpu with 4 alus. Both intel and amd could make this step. Another trick is to update the classic on the fly x86 - risc converter to take advantage of more alus.