The PS3 system software update 4.92 is now available to download, with Sony noting that users must update their console for the latest Blu-ray encryption key.
scph5500.bin (PS1 JP BIOS), scph5501.bin (PS1 US BIOS) and scph5502.bin (PS1 EU BIOS) are required. psxonpsp660.bin (PSP PS1 BIOS) and ps1_rom.bin (PS3 PS1 BIOS) are optional.