One of the most stunning outcomes of the now month-long oil spill in the Gulf of Mexico is the utter reversal of corporate images it has generated. At once, Exxon — for two decades tarred as the callous, greedy and dirty culprit in the Valdez oil spill in Alaska — is regarded in expert circles as the squeaky clean, state-of-the-art, cutting-edge model of safe, environmentally friendly oil drilling. And BP — which spent tens of millions of dollars under former CEO John Brown successfully branding itself as the green, publicly interested conscience of the industry — is now the poster child of the devil-may-care, dollar-grubbing, environmentally and labor unfriendly oil company.