I saw the film last night. I don't go to movies at the theater much anymore, so this was a treat. I found it quite disturbing. Phoenix was incredible. For me, the movie was not about the violence but about mental illness and the internal struggle he has with himself and with society. He is the outsider. It is a very dark film, beautifully made, with haunting music, great cinematography, and Oscar worthy acting. Many of the scenes show the Joker alone, isolated, inside his mind, and outside of society.
I loved it and recommend it. It is not a casual watch. Interestingly, some of the riot scenes in Gotham toward the end of the film remind me of actual events seen on the news in some of our cities, and what we are now seeing in Hong Kong. The Joker was a flashpoint, and thoughtful people who are criticised because they view things differently from the way those in power would suggest, they become quiet and don't share their thoughts with others. They turn inward and search for ways to act out. These people can relate to the character, and once that flame is ignited, stuff happens. We this this today, all around us. It's a powerful film and reflective of our times.