As we can see, they are the unoffical, unappointed "religious police" in Catholic circles right now. Anything that is not 100% in line with the Vatican point of view is "Un-Catholic". Their big focus is on Catholic schools, colleges, and universities.
The National Catholic Register is redoing their website, but they have a list of "Mandatum Schools", they are "approved" colleges (by the CNS) who are supposed to be wholey "Orothodox" in their teachings and 100% in line with the Vatican hierarchy.
http://www.ncregister.com/features/mandatum.htm (link may work sometime in the future)
That is how the CNS works, they are quick to attack any school and brand them as a "Non-Catholic" school if it does not fit the "Orthodox" definition on ANY little matter. Debate and discussion do NOT exist with them. Thinkers are really not allowed, and in this example it does allow for academic discussions.