http://www.theregister.co.uk/content/3/32264.html
"[Lisa] Su's role suggests that IBM may be looking to extend its PowerPC processor family with HyperTransport. While IBM's 64-bit PowerPC 970 chip doesn't support HT, the chip's chief 970 customer, Apple, does use the next-generation bus to connect its IBM-manufactured North Bridge chip to its South Bridge part. "
"[Lisa] Su's role suggests that IBM may be looking to extend its PowerPC processor family with HyperTransport. While IBM's 64-bit PowerPC 970 chip doesn't support HT, the chip's chief 970 customer, Apple, does use the next-generation bus to connect its IBM-manufactured North Bridge chip to its South Bridge part. "