I have no idea what you mean by "salted, but not hashed".

Salting is when you append a known value to a password before hashing it in order to increase the work an attacker has to to when trying to brute-force hashed passwords. To "salt, but not hash" would presumably mean storing a salt value alongside an unhashed password. I can't conceive of a reason anyone would do that.

Hashing is an irreversible process that turns the password into a fixed-length hash. It can't be undone other than by hashing all possible passwords and comparing the output to the known hash.

Encryption is when a reversible process where the plaintext, in this case a password, is changed in a complicated way that depends on a key. The output, however, along with the key can be used to recover the plaintext password.

What Sony is saying in that press release is that the passwords were hashed, not encrypted. That is the standard, recommended way of storing passwords, it's not necessary, or desirable for the server to be able to recover the plaintext password.

It would make sense for something to be hashed, but not salted. This would indicate that the passwords were not hashed with a salt, and it would make a brute-force attack easier. It does not, however, make sense to say that something is salted, but not hashed. Unless you're talking about a potato.