The bat voice.
The fall from a skyscraper that two people just walk away from.
That Bruce laid down the bat-pod to avoid pedestrian Joker, when he could have blown him up from down the block. Stupidest bat-move ever.
That ten seconds later Gordon didn't put a bullet in Joker's brain pan.
That Gotham's finest didn't see the gut-bomb coming from 10 miles away like I did, the moment the guy first complained about his pain, not to mention putting some run of the mill thugs in Joker's presumably high-security cell with him.