For those worried that their passwords may have been compromised, please note that this site's database does not store them in a retrievable form (for the technically minded, it's a randomly-salted one-way hash).
Indeed vBulletin hash security is rather good. However to be 100% technically accurate it should be: "in a easily retrievable form". It's possible to attack even salted vBulletin hashes, just a lot slower. Of course you'd need to get hold of the hashes somehow, first.
