A brief overview of the PPC 970 processor can be found at here. This page also offers an explanation of the basic architecture differances between x86 and PPC processors as well as reasons for benchmark discrepancies.
For a more thorough write up of the features of the PPC 970 processor go to parts one and two of the Ars Technica in-depth evaluations. These links are for those wishing to go into more detail.
