The linked Washington Post article doesn't explicitly identify the study, so I will do so.
Blogs and Military Information Strategy (9 page PDF) by James B. Kinniburgh, Major, USAF, and Dr. Dorothy E. Denning. From IOsphere, the publication of the Joint Information Operations Center. Summer 2006.
Here, in a study published in June 2006 by the military's Joint Special Operations University, two "information warfare" specialists mull over how the U.S. armed forces and intelligence agencies might influence opinion overseas through foreign bloggers:
[I]t may be easy for foreign audiences to dismiss the U.S. perspective with "Yes, but you aren't one of us, you don't really understand us."
In this regard, information strategists can consider clandestinely recruiting or hiring prominent bloggers or other persons of prominence already within the target nation, group or community to pass the U.S. message. . . . Sometimes numbers can be effective; hiring a block of bloggers to verbally attack a specific person or promote a specific message may be worth considering. On the other hand, such operations can have a blowback effect, as witnessed by the public reaction following revelations that the U.S. military had paid journalists to publish stories in the Iraqi press under their own names. People do not like to be deceived, and the price of being exposed is lost credibility and trust.
An alternative strategy is to "make" a blog and blogger. The process of boosting the blog to a position of influence could take some time, however. . . .
There will also be times when it is thought to be necessary, in the context of an integrated information campaign, to pass false or erroneous information through the media . . . in support of military deception activities. . . . In these cases, extra care must be taken to ensure plausible deniability and nonattribution, as well as employing a well-thought-out deception operation that minimizes the risks of exposure.
And from part of the IOsphere article that the Post neglected to cite:
Some of the possible techniques we have explored in our discussion of the military use of blogging require a certain degree of subtlety, finesse, and yes, covert action. By giving military blog-based operations to the Intelligence and special operations communities, these uses become less risky and more feasible. However, military operations must necessarily remain only a part of a larger effort. Given the current state of US and international law, and the distribution of the necessary authorities among many (often competing) government agencies, any future conduct of influence operations through the blogosphere will require a truly integrated interagency approach, and thus belongs properly at the national level as a part of an over-arching strategic communication effort.
One of the significant limitations of this article, as an initial foray into military use of the blogosphere, is that much of the information available concerns American blogs, run by Americans, largely for an American audience. Military use of the blogosphere must necessarily focus on foreign blogs, bloggers and audiences. However, because some factors, such as the scale-free nature of the Internet and the psychological basis of influence are universals, we hope to lay a general basis for military use of the blogosphere that can be adapted to specific tactical circumstances by information operators.