Still better than a full dump à la WkiLeaks, but the big question is whether the journalists have the OpSec skills to avoid leaking the documents to other governments.
It doesn't matter if it was directly or through an intermediary, everything that Snowden gave to journalists, Snowden leaked to the public.
Why not just leak documents related to that one issue? If he had, I would not hesitate in the least to call him a whistle blower, and in fact I think he'd be living as a free man right now if that were the case.
Second, we don't know the number of potential documents, nor how they may have been divided among those to whom they were disseminated.
Addressing the first point, it should take work and review, on an ongoing basis, to re-affirm the classification of that material. By default there should be a /reasonable/ and /short/ expiration time. If it costs too much to keep those secrets than that in and of it's self is a reason for not HAVING so many secrets to keep!
The cost, otherwise, is to our freedoms; to the very liberty for which our government is supposed to be protecting.