I was left disappointed in all expectations, and just generally disappointed. (Although Russell Crowe did sing for a bit, so there was that...)
Note: spoilers ahead
To begin, I'll start with the most obvious: acting. As expected from a cast of Anthony Hopkins, Russell Crowe (when singing is not involved..), Emma Watson, etc., the acting was all top notch. Even when the plot got to be pretty meh, the actors and actresses did a great job with what they had.
As to that -- what they had -- well, for starters, it was too long. Coming in at around 2.5 hours, the film seemed interminable. I don't mind long movies, if there's a reason for the length. But there seemed no justification for the extension of Noah. The plot took twists that were neither compelling nor necessary, but served the dubious purpose of dragging out the film.
Noah includes a subplot that I have found no evidence existed in any form in any of the Big Three (Judaism, Christianity, Islam) tellings. This is probably the film's biggest weakness (and also the reason why it lasted so much longer than necessary), because the subplot was not very good: Noah decides to exterminate his own newborn granddaughters at their birth, so that his family will be the last family of humans. He makes this decision because he believes (mistakenly, as it turns out) that the Creator regrets creating humanity, and so it must be eliminated. And Noah believes that the Creator has chosen him for this sacred purpose. It's worth pointing out that all this confusion might well have just been avoided if the film had followed the route of the story -- that G-d/God/Allah actually told Noah what was going on, rather than the idea coming to him in vague dreams and hallucinogenic fueled visions. This is the culmination of a not-very-subtle and not-very-nuanced environmental subtext that follows the entire film (good people are vegetarians who eek out an existence off the land; bad people are meat eaters, miners and industrialists who destroy the earth; there is no middle ground portrayed). It in turn raises another set of problems -- namely, that of re-population occurring as a result of unions between uncles and nieces (as if the story's first cousin-romance wasn't creepy enough...). (It additionally ignores a giant logical flaw -- if Noah was willing to kill his baby granddaughters because they might survive to womanhood and reproduce, why would he spare his magically cured/now fertile daughter-in-law?)
At any rate, that tangent added, IMHO, way too many minutes (and not much else) to the film. It also seemed to be somewhat self-defeating, and indicative of the self-defeating nature of the film, as it really negated the entire point of the story. Noah wasn't a good person who implored the people to act rightly and avoid death, whose own goodness resulted in his and his family's survival. He was a potential murderer who self-righteously turned up his nose as people drowned (instead of imploring them to join him). He was a self righteous murderer who would kill his own granddaughters in their weeping mother's arms in order to carry out self-imposed dictates.
I'm not saying there isn't potential in a retelling to examine the moral implications of the story...rather, that in adding so much that was never a part of it to begin with, it's easy to ignore the question. It's easy to dismiss the idea of babies drowning for the crimes of their parents, amidst a story complete with stone giants, Noah's wife reading tea leaves, Methuselah practicing healing magic, and Noah plotting to murder his grandbabies. The story was treated too irreverently, handled too haphazardly for any of Noah's (sporadic) depth to make an impression where it might otherwise have done. Any question of the morality of drowning men, women and children, of punishing the drowned babies for the crimes of their parents, was lost in a tangent that added nothing to the story.
And, to be honest, I didn't care for how the film was presented as a Biblical movie, but effectively turned the entire story on its head by making Noah a reckless, homicidal kill-people-to-save-the-earth hardcore environmentalist (seriously, did Aronofsky get his environmental ideas from watching Fox News' coverage of environmentalists? At points, it watches like a parody of environmentally concerned people). It seems like false advertising. If you're playing to religious audiences, promising them a religious film, you should deliver. Or you should run with a secular Noah film. But trying for both, to get the religious viewers' ticket sales while making the hero of their story a villain? It seems like cheap exploitation.
Now, I should be clear, I'm not complaining that the story critiqued the Biblical accounts. I think there's plenty of room for critiquing a literal read of that story, and I don't think any ideas should be above criticism. Would an openly secular Noah have pissed off just as many -- maybe more -- Christians than this one did? Sure. But I think Aronofsky should have chosen one or the other -- one that stayed true to the general spirit of the religious story (even if that means including stone giants [cringe]; obviously, it by necessity can't be exactly like any one of the three tellings, and liberties will need to be taken...but to turn a clear cut hero into, at best, a quasi-hero?) or else went in whatever direction he chose -- and marketed it accordingly.
As it is, from a financial standpoint, he seems to have a winner. It's opening weekend was pretty successful. There are Christians who love it. Atheists who love the far right Christian response to it. Movie goers in general who find it compelling. I was not, however, one of them. The film seemed too bloated, often too pretentious, and, no pun intended, ultimately too shallow to merit more than an "eh".