Broadly speaking, there are two groups of people likely to go and see the movie Noah.
In group 1, we have those for whom the story of Noah's Ark is a parable at best and a flimsy fairy tale at worst. To you I say this: whether or not God is real, within the reality of the movie there is no doubt. If you can believe in lightsabers and the force for as long as it takes to accept a story in the Star Wars universe, you can accept, for two and a half hours, that a divine being who wants to drown His own primary creation is very real inside the world of this film.
In group 2, we have those for whom the tale of Noah is holy writ, and possibly even the literal history of mankind. To you I say this: EVERY movie about history takes liberties. All are staged interpretations, and none are 100% exactly as they actually happened. Before they were written down and codified, it isn't hard to imagine that the various fireside oral tellings differed from one another. That does not invalidate the final moral.
Knowing that, then, how do we judge Darren Aronofsky's Noah?
There's no easy way to do it objectively, so anyone offering judgment might as well start with the personal and proceed from there.
Noah begins with all the bombast of the most important story ever, which to some, of course, it is. Loud drums, a grand cosmic canvas, the serpent of Eden shown in neon green, Cain's murder of Abel in silhouette, and Genesis prior to Noah's birth shown in broad, grandiose strokes. Director Darren Aronofsky will turn again and again to the creation myth in quick cuts, like the breakfasts in Requiem for a Dream, until he finally, late in the film, has Noah tell the entire tale, and all of creation is encapsulated in such rapid time lapse that anyone over the age of 12 is at risk for seizures merely beholding what is onscreen at that moment.
For at least the first half of the film, we get the Image Comics version of the Old Testament. Fallen angels known as the Watchers, referred to in Genesis as "the sons of God" in both Bible translations I looked at prior to writing this review, appear as giant rock monsters; shining angel spirits trapped within the sludge of the earth (trust me: Rob Liefeld, a fan of both the Bible and giant heroic rock monsters, will love this movie above all others in 2014). Tubal-Cain (Ray Winstone cosplaying as Mickey Rourke), a minor figure in the Bible noted only for creating things from metal, is now an evil king who murdered Noah's father and wishes to corrupt his son Ham. Knives penetrate bodies, armadillo-dog hybrids get struck down, and trees spring from miraculous waters.
Claims that this movie is environmentalist and therefore bad strike me as silly - how do you show that mankind has ruined creation without showing said creation as despoiled? Aronofsky's view from space of the Earth as a fruit gaining mold might be a bit dramatic, but if anything, the story justifies the fact that whatever man can do can be reversed if God decides to hit the reset button and drown everyone. Besides, the knock on environmentalism from the right tends to be that it's anti free-market, and there's no indication that what Tubal-Cain is doing resembles that in any way - he enslaves the Watchers, rapes women and tears live animals apart while over-mining the earth for a magical exploding material that might as well be called Unobtainium, or Kerium.
God - or as he is solely referred to here, the Creator - never speaks to Noah directly. Instead he delivers dreams, visions, and via psychedelic tea prepared by Methusaleh (Anthony Hopkins) the instructions to build an Ark. For those who wonder why said Ark doesn't immediately turn into a gigantic animal toilet or buffet, it's simple - Noah's wife burns weed that makes them hibernate. It may not be marijuana, but it is clearly the good shit.