Apple might have been working on designs like that just in case the 970 didnt pan out. Just keep adding processors untill they could find a new/faster proc, and thats why we heard so many rumors.
Introducing the new PowerMac, with either 4, 6, or 8, 1.42ghz powerpc G4's. Now featuring support for iWalk, color video iPod, iSee, iQuicktake, and the iNewton. All new PowerMacs come preloaded with rendezvous enabled iTunes, iWorks, and of course
OS X 10.3, A Panther that has "piles".
Sorry I could not resist.