I just wanted to share some insights of the HDD encryption, I gained in the last days:
It seams the encryption is sector(512 bytes)-wise, meaning that each sector is encrypted by the same way. There are no further dependencies of the encryption key to things like the sector number (but of course the key depends on the specific PS3).
In each sector the data is encrypted in 16-byte chunks. There are 32 of these chunks in each sector and every chunk is encrypted differently. Whether the algorithm change or the key, I don't know yet.
The chunk encryption is not a simple XOR with a key, it actually depends on the data in the chunk. I think it is also not a simple substitution chiffre, since for 16 bytes, the substitution table would be far far too big to store anyway. I'm currently investigating whether it may be a linear function of the input data.
That's what I know so far, comments, any ideas?