Justin lets us know that Arup is going to write a series of papers on how to secure Oracle to be published soon on OTN. This should be a great series. I have been a fan of Arups writing since he wrote the HIPAA book. I also read hos 10gR2 new features series of papers and also I just bought his recent new PL/SQL for the DBA book which includes some excellent sections on Oracle security.
In the meantime anyone wanting to check if they have any vulnerable default users with known default passwords should head over to my Oracle Default Password List and then my tool for checking - Oracle Default Password Auditing Tool.
I am really looking forwards to Arups papers.