Interesting DG.
I contemplated seeing this movie when it came out, but was put off by David Denby's New Yorker review. Denby is a slightly more respected member of the film critics guild than Ebert, and he didn't seem to appreciate Dogville's finer points either.
[The full length version, which I read at the time, is not available online; I pasted his brief excoriation for your amusement.
]
Dogville (2004)
"Pedantic, obtuse, and unwatchable, this three-hour exercise in inept avant-gardism, written and directed by Lars Von Trier, is set in a town without walls, streets, or air—a conceptual Depression-era nowheresville in the American Rockies in which obvious allegories of conformity and viciousness are acted out by a cast reciting an inhuman language into the dead silence. We might be present at a nightmarish school play. With Nicole Kidman as the poor waif who eventually takes her revenge, Paul Bettany as a weak-willed artist, and a variety of other excellent actors submitting to Von Trier's solemnly stupid rituals of betrayal. The pompous narrator is John Hurt, who sounds like Henry Fielding wishing he had a tankard in his hand."
That said, I might pick it up now and judge for myself.