I've just done measurements of my PS3 vs my Oppo DV-970HD. Both are connected via HDMI, YCbCr 4:4:4, into a Crystalio II and then out via HDMI->DVI at 1080p60 to an LVM-47w1. Oppo is 480i out, PS3 is 480p out. Both were playing copies of the same GetGray disk, displaying the 10% Full Field and 100% Color Window patterns. Measurements were taken back-to-back with a Spyder2 using CalMAN software. Separate from measuring, I also displayed both sources simultaneously using the Crystalio's picture-by-picture support; viewed this way, all of the PS3's gray patterns (above 0%) were lighter/whiter than the Oppo's, including 100% white. Attached are the recorded measurements.
gray.pdf 157.935546875k . file