I went to see Pirates of the Caribbean: Dead Man's Chest and Michael Mann's Miami Vice. I enjoyed Pirates, very similar to the first one I felt. I'd recommend seeing it. It's fun and entertaining. Miami Vice was excellent. Michael Mann seems to be exhibiting his auteur desires more and more with every film. I think that most of these are good things and only a few bad. Miami Vice looks like a Mann film from the first frame. The cinematography is fantastic. The film has Mann's signature style of night time lighting, car interiors, headlights, exterior halogen lighting, and dark naturally lit scenes. Miami Vice was filmed on DV like Mann's most recent film, Collateral.
I think that you can see an arc in Mann's films from Heat through Collateral and now with Miami Vice in regards to realistic violence. Heat, one of my favorite movies of all time, has what I still believe to be the greatest shootout in film history in which Al Pacino, Robert DeNiro, Val Kilmer and Tom Sizemore shoot it out in downtown Los Angeles. The strength of this scene is it's shocking realness. Collateral follows this with a number of scenes that take this to the next level. The ultimate example of this is the scene in which Tom Cruise's character returns to the cab to find Jaimie Foxx's character being beat up by thugs in the alley. Tom Cruise brutally kills them in a frighteningly realistic manor lacking passion or excitement. He takes these mens lives and it's boring, which I think is amazing. Miami Vice continues this trend with a number of scenes of amazing realism. The shootout in the trailer caused, in the audience I was watching the film in, a huge response.
The soundtrack to Miami Vice also continues a theme of very bizarre music selections in Mann's films. I am glad he does it and I think it adds to the films, but I can't say that I like the music (except for all of the Moby tracks).
In summary, if you're looking for a good time and like the first Pirates of the Carribean, see the second one, I enjoyed it. I highly recommend you see Miami Vice in that I think it's an important and beautiful piece of art, in addition to being a very enjoyable experience.