Ref:
Identity Theft: Protect Yourself...
Select a good password. "iLoveMikey" is a bad password. "qicITcl}" is a great password. You can see the problem though -- great passwords are hard to remember. So compromise: never include full English words or names; always include a mix of uppercase and lowercase letters and numbers; always make sure that the password is at least 8 characters long. 'Macintosh' is bad, 'Mac7T0sh' might be good, and probably easier to remember.
Bottom line: pick a random looking password that YOU can remember, but that THEY would never guess -- and assume that THEY are always really great guessers.
...