The article you mention “The 60 Minute Network Security Guide (First Steps Towards a Secure Network Environment)” covers a few great and time-proven methods for hardening your system. However, the last REAL update to it was 29 March 2006. (in computer years, thats a LONG time ago)
Using the concepts in the document are great, but with the official IANA IPv4 depletion announcement, you also have to add in, at least from the Networking (Routing/Switching) perspective, new filters/ACLs for IPv6-formatted addresses and other technologies and standards that have come about since the document was published.
Another great over-view can be found at www.net-security.org