In all honesty, I think that Snowden's continued media presence is actually hurting his cause. Between the smear campaign by the current administration (and press) and the casual comments he's made that has lost people on his cause, he might be keeping the story going, but the story is shifting more to one of ad hominem, and less of one on the issue at hand.
The populace at large is terribly bad at keeping issues like this in pragmatic focus. Too few realize that even if Satan himself had been the one to leak this information, that we're all better off for having known it; and I'd hope that it would give some Americans pause enough to consider the actual implications of the Constitution; whether or not the government can govern through the consent of the governed, for example, if they have secret governings, or whether or not the non-delegation clause of the Constitution should actually allow for the NSA (staffed with officials we can't vote in or out) to write laws, when the Constitution specifically enumerates that law-making power resides in Congress alone.
So while ultimately, all that boils down to is ARGHHHHH MY FOURTH AMENDMENT, it's also an opportunity to have a larger discussion on what that fourth amendment actually means, and what other parts of the Constitution might come into play, and whether or not it's fair that the government has extended its power to such the degree that we can have 300 different "agencies" like the CPPABSD (Committee for Purchase From People who are Blind or Severely Disabled -- they regulate how many coke and vending machines other government agencies should purchase from strictly blind or severely disabled sources), each of which is allowed to write laws that do not pass Congress, do not pass the house, and aren't subject to the oversight of the citizenry. The FTC, FDA, EPA, NTSB, etc., have all arguably affected each of our lives in some non-trivial ways, and those officials are just there, persisting, whether we like it or not.