The following are pictures of my drivers side and passenger door frames. Drivers side has developed a crack at the weld point with rust peeking through and passenger side looks like it is developing one as well. Everyone check your door frames for similar cracks. I have shown it to my service managee and he has taken pictures and will be talking to the dealer rep. to see if they will possibly repair it. I still have another year left for warranty on corrosion/rust. Have not had an estimate done yet. FYI keep your eyes on this and post it and approach your dealership. This is obviously a manufacturing defect so it will be interesting to see what Nissan tells the dealership.
No amount of strut and sway bar installation or "lack of bodyflex" would cause such structural failure (I assume worst case scenario as an excuse by Nissan). It is a tack weld point, which I assume is performed by a robot at the assembly plant.
Driver's Side:
Passenger's Side:
