I'll just chime in here and then take off. Someone else expand or "fix" what I say. The GPU in both the GC and the Wii weren't really customized, they just came from a different graphics vendor that was bought out by ATI mid way through GC development. That graphic vendor had decided on creating the TEV unit for lighting and shading via hardware code. For comparison nvidia had chosen programmable shaders for their lighting and shading and Sony had chosen a custom method involving co-processors and whatever GPU functions Toshiba built them (I think it was Toshiba). Saying the GPUs in the GC and Wii are heavily customized is like saying the GPU in the Dreamcast is heavily customized despite being an off the shelf PowerVR card. Graphics at the time didn't really become unified until the Geforce 3 and Radeon 9000 came out. It's been update and iterate since. Though I am talking out of my ass based on what I've read about. To say there's been no customization is foolish, but to think that Nintendo went out of their way to customize graphics is also foolish.
