Bump from Gotham City, since I've seen the movie.
I thought it was fantastic. Quite heavy on the subject matter, and slow at times, not sure it's gonna be one of those movies one's gonna watch multiple times, but it was great and heavy hitting.
Very stilish, obviousl saturated and color corrected to death, but it was a gripping and dramatic journey into the descent into total and violent insanity of an already troubled man. I thinkl the mashup of genres was done quite nicely - heck, you could re-do it as a stand alone movie about a random mentally ill person, removing all the Joker / DC references, and you would need to change only 10% of the film.
It had a gripping atmosphere, the cinematography was stellar with many nice shots (the stairs, the subway shots also...), and I don't think the Wayne mentions were overdone. I didn't even realize the butler was Alfred himself at the gate scene where Arthur talks with little Bruce, I thought he was a random servant. The ending was fantastic, that's basically when the movie became essentially "Joker begins".
I personally would have ended it there - the Joker rises on the same night Bruce gets his parent killed and starts his path to be Batman. I didn't care for the little coda in the asylum, it would have been perfect to end it in the streets.
By the time Bruce becomes a grown man (and Batman along the way), this Joker would be old... but for all we know someone else could take inspiration from Arthur and become the "next" Joker. And it's not like this movie has to have a sequel anyway.... it works damn fine on his own.
I'm a bit puzzled at all the strong reactions and fears it would inspire violence.... I thought the movie struck a nice balance between letting you symphatize with Arthur (it was brutal to see him being told "society doesn't give a shit about people like you" from her psychiatrist) and showing that yes, he's a crazy and deranged violent guy, who totally deserves to be locked up in Arkham. If people see this movie and feel the need to down clown mask and start riots the problem is with them, not with the movie.
Oh, and Joaquin Phoenix totally deserves any award there can be for his performance!