I think you'll find the most info in this multiple page FAQ at:
http://cube.ign.com/articles/522/522559p1.html
from the FAQ:
Rumors abound indicated that Nintendo could separately be working on two systems and that ultimately one would be chosen for retail. System 1 allegedly featured a 2.7GHz PowerPC G5 processor, 512MBs of RAM, and a 600MHz graphics chip. System 2 allegedly featured dual 1.8GHz PowerPC G5 processors. 256MBS of DDR Main Memory RAM, 128MBS of GDDR3 Video RAM and a 500MHz graphics chip. Both systems allegedly featured a built in 15GB hard drive. As of this time, these rumors cannot be validated.
As for confirmed stuff:
In March 2005, Nintendo confirmed that both IBM and ATI would supply the CPU and GPU respectively for the Revolution console.
The IBM-created CPU is called Broadway. The ATI-developed GPU is called Hollywood. At the March 2005 Game Developers Conference, Nintendo president Satoru Iwata explained the reasoning behind the titles.
"With IBM, we are creating Revolution's core processor, which we have codenamed Broadway because Broadway is the capital of live entertainment," he said. "With ATI, we are developing the graphics chipset, codenamed Hollywood because Hollywood is the capital of movie entertainment. With Revolution, we are determined to create the new capital of interactive entertainment."
It was also confirmed by the big N itself that the Revolution will be backward compatible with GameCube software. Since the GC uses a modified G3 and that Nintendo is still working with IBM, it's pretty obvious that the Revolution's cpu will also be PowerPC based.
The Cell processor to be used in the PS3 is also based on the PPC so it means all three next-generation consoles will use PPC variants. It will get harder and harder for Mac bashers to dismiss the PPC platform.
VL-Tone
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