Two dozen Arkansas homes evacuate (video below) as an Exxon Mobil pipeline ruptures, pouring an estimated 84,000 gallons of Canadian crude into their neighborhood on Friday about 20 miles north of Little Rock. Police report that the oil gushed for 45 minutes before being stopped. Meanwhile, Texas landowners join activists in the Keystone XL pipeline blockade. Events unfold as President Obama considers the fate of the pipeline, with the Arkansas crisis providing further impetus to the argument as to why the pipeline project should cease. A much-discussed Canadian op ed here at the NY Times from Thomas Homer-Dixon.