ShadowRunner
Veteran
I had this bookmarked from some time ago. Nothing about hte PS3, but goes into some depth about how the gamma curve is implemented on the 360 vs PC
http://www.valvesoftware.com/publications/2008/GDC2008_PostProcessingInTheOrangeBox.pdf
Im pretty sure i remember hearing PS3s implementation is same as PC. Screenshots across all 3 platforms often show it i believe.