While "Born To Be Wild" is playing in the background, and the Impala is driving toward SucroCorp to begin the raid, two people can be seen riding in the car. However, after the Impala crashes into the company sign, only Meg emerges.
Bobby's flask always had a leather cover. When Dean throws Bobby's flask into the fire, the leather cover is missing. This would mean that Bobby is still connected to the real world through the leather cover.
When Sam pours the blood on the bone they use to kill Dick, he pours it on, opposite of the sharp end.
Kevin could have not known about Dick's plan with the creamers because he stopped overhearing the meeting between Dick and the delegates and gets caught by Dick's assistant (Susan) BEFORE Dick talks about the creamers.
When Dean, Sam, Meg & Castiel regroup back in the cabin, Dean says that all the Leviathans turned into Dick due to "they all downloaded Dick's brain". In reality, they used Dick's arm.
When the Impala is heading into Sucra-corp there are 2 people in the car but, when it crashes through the sign, only Meg is in the car.