See bottom of post: This essay was deemed UNCLASSIFIED and approved for public release by the NSA's office of Pre-Publication Review on 11/21/2013 (PP 14-0081).
Hmmm... where do we find out about all the CLASSIFIED blog posts? NSA internal forums? Any place where there's a summary of these reviews as metadata, hence leaving the content "CLASSIFIED" ? Who is watching the watchers?