Rick, as you know Cg is Nvidia's high level programming language for pixel shaders.  Porting them to Cell, the PS3 CPU would make little since.  I assume ZDNews's article meant the PS3's GPU, not Cell.
Unless my comment is true, which I doubt... 
Also, my guess is that Metrowerks will be involved in Revolution's
tools.  Considering that Metrowerks is used for N64, DS and GC development.