Visible crew/equipment: In the scene when Spider-Man is chasing a truck stealing OsCorp's plutonium vials, the truck, driven by Aleksei Sytsevich, crushes one of the police cars. The scene cuts to the left side of the truck crushing the police car. A moment later, it cuts to another angle. Here you can see the camera equipment on the left side of the truck. (00:08:20)
Continuity mistake: After Electro launches Spidey against the police car, the huge dent on the door gets smaller between shots. (00:55:40)
Answer: Peter didn't set out to kill Electro, but he has to stop him somehow. Overloading him is pretty much all Peter has to work with in terms of stopping Electro's rampage. He doesn't know what effect it will have on his opponent, but he hopes that it will serve to stop him in his tracks, which it does. Had Peter set out with the specific intention of killing Max, that would indeed have been wildly out of character, but he didn't - he simply did what he had to do to stop him. It's unlikely that Max is actually dead anyway; it's well known that Sony intend to bring the Sinister Six into play in upcoming movies and Electro has been a key member of most incarnations of that team, making it highly likely that he'll be back.
Tailkinker