If it's anything like Cell, it's just a bunch of fairly boring configuration information. If you want to dig in more it's called the "Configuration Ring". It's an about 2kbit SPI ring that has stuff like memory timings, and all the stuff that might get fused off for binning. On the PS3 you could try and turn on the SPE that was disabled by playing with the config ring, and see if you got lucky and had a perfect chip.