That may have been true for whichever couple of days the talking heads devoted to the unfortunate Ms. Dean, but it simply isn't borne out over the long haul. If you look really hard, I doubt you can find a single piece about Dean that was produced today, while most outlets have several about Snowden.
You can't find a piece about Paula Deen today because the attention has shifted to Prince George. Which, by the way, is exactly the point: While there are people who care about Snowden, NSA, etc., they are not currently any kind of substantial part of the public. We all ignore that at our peril.
The fact that Snowden may be a larger-than-normal individual news story doesn't change the fact that the story doesn't capture public attention in the face of the multitudes of other news stories continually cropping up and then going away again.
Prince Who? Look, I'm an American. We fought several wars to confirm that we don't have to give a flying fuck about King George III or any of his syphilitic inbred descendants.