Once the MSM discovers that Carter and Clintoon did the same thing, this will quickly disappear just like the litany of "We got Bush cornered" stories go away. It will be replaced by a new Bush hating story before Jan 1, my guess. And yes you are probably right if the leaker is a congresscritter they won't be touched. BUT the DOJ can go after "author Risen" and the NYT IMHO.
If the DOJ DOESN'T go after the NYT reporter to see who the leaker was it SHOULD invalidate the Fitzermans case on Plame.
But it won't.