Problem is, like Rangel prior to the midterms, the Dems and their dutiful sycophants in the MSM will 1--keep it as low key as possible, 2--bury it as quickly as possible. OTOH, were this Gonzales or Ashcroft, this would already have been in every outlet and the front page of the NYT above the fold for weeks, with the DUmmies calling for "Chimpeachment", frog marching, etc.
It's currently in the Dems best interest for this to go away as quickly and as quietly as possible. Issa should hold off on this until well into primary season. Gather evidence, get statements, give Holder enough rope with which to hang himself, and then around convention time, snap.