What gives? Jeff Jacoby has some thoughts on the matter:
Gibson and Stone are both guilty of indulging in rank anti-Semitism (for which both promptly "apologized"), but only Gibson was buried under a newsroom avalanche of outrage and disgust. What explains that glaring difference? Surely the media don't think Jew-baiting is intolerable only when it comes from a right-wing Christian like Gibson. Surely they wouldn't overlook Stone's noxious rant just because he is a pluperfect left-wing activist.
Surely that can't be the explanation for so disgraceful a double standard.