This guy says something different
http://arstechnica.com/news.ars/post/20060322-6436.html
The PPU will take load off of the CPU by bypassing the physics calc results straight to the GPU and onto the screen...Much like how the GPU sheds load off of your CPU...
It also mentions 60 software developers making over 100 games... Some computers are already shipping with these from such manufactures as Falcon NorthWest, Dell, and AlienWare...
It really could be interesting to see what happens with this technology