For anyone that thinks there is actually a problem here, what could the motivation or mechanism behind this "blackout" possibly be? Significant parts of the US media have been reporting pretty well on Snowden for a long time now.
Journalists depend upon access to government officials to report news on government actions..
No Access to those officials virtually decimates both the Media firm income and the journalists income
so what
If the whitehouse denies access like that - cutting off some of their own ability to disseminate propaganda - the journalist can simply write on the subject anyway.
Even better, while other journalists are busy copying down the usual stuff, the "cut off" journalist can run the "government interfering with the Free Press" story. Loudly.
Denying "access" merely changes what the story will be about.
And what do you complain about? That the government is not leaking you information anymore? That anonymous sources aren't taking your calls?
One is deliberately leaking the story line that the administration wants published, but for whatever reason doesn't want to be directly quoted on.
The other is the conscientious leaker, who wants to get the truth out but fears for job/safety if he went "on the record."
The former can be directed to "leak" only to favored media outlets. The latter cannot.
What will be reported on? In a case like this, the run with the information they have.... from Snowden. If the government decides it doesn't want to tell it's side of the story (officially or unofficially through "sources"), then they let the accusations stand without a challenge.
Oh, and you may remember a time when journalists got their own information ("investigation"), instead of relying on PR offices.
I am constantly amazed how the government (and many big businesses) get away with this obvious bluff. There is simply no way they would withdraw from the public debate.
The government uses implicit threats of retaliation as deterrence.
You made an assertion. Back it up.
That the government doesn't like Snowden being cast in a favorable light or that it uses mechanisms to deter people from doing so?
A good place to start for the latter is chapter 1.3 of "Manufacturing Consent"
[A former British official] described how the Foreign Office manipulated a willing media. "We would control access to the foreign secretary as a form of reward to journalists. If they were critical, we would not give them the goodies of trips around the world. We would feed them factoids of sanitised intelligence, or we'd freeze them out."