The movie is written and directed by John Turturro, and produced by the Coen brothers. The story is fairly basic, in some ways - a guy cheats on his wife and regrets it. The cast is outrageous - James Gandolfini, Susan Sarandon, Kate Winslet (with a Cockney accent, a lewd mouth and a shock of red hair), Mary-Louise Parker, Eddie Izzard, Christopher Walken, Mandy Moore (I am consistently impressed by the bold acting choices either she or her agent is making), Steve Buscemi, Aida Turturro (I love her, I really do), Amy Sedaris... it's star-studded, to say the least. And it's a musical! And it's just so... bizarre. Really. I spent about half an hour with my mouth open, struck dumb with astonishment. But while it's outrageous, it never goes too far, I think. Somehow it manages to work. And the dialogue, while cheesy and ridiculous at times, has this strange sort of poetry to it.
You've got to check out this movie. It's wild.
Oh yeah, also - check out the deleted scenes in the bonus features. And the featurette thingy. They're actually worth it.