As a general rule, film critics at any level do not go back and second-guess themselves, at least not at length.
The reasons for this are myriad. The noble-sounding one, the one you hear most-often, is that it's improper because movies are made for the first time you see them and thus that original set of impressions is the only honest one.
The significantly less noble-sounding one is also the one more likely to motivate the action: To "re-review" calls into question the delicate barrier that most critics, self-styled or otherwise, believe exists between their analysis and the "I liked it/didn't like it" impressions of everyone else. So much of The Film Critic's self-image comes from the facade of Immediate Intellectual Authority: Anyone can decide whether or not the movie was good after a few weeks of turning it over in their mind - The Film Critic is supposed to be better than that, posessed of a film-based intellectual so keen that his expertly-considered, fully-formed summation of quality is ready the moment the house lights come up.
In looking back over my reviews for the various Oscar nominated films this year, a nagging issue stands out that I cannot ignore: I was much, much, much too generous toward "Babel," awarding it 7/10 at the time. That review will still stand, as it is the accurate representation of my feeling upon writing it. But as this re-thinking comes later, I have no issue with offering my revised thoughts.
Stated plainly: The movie just doesn't work. It's best segment, the one following Rinko Kikuchi's deaf-mute Japanese teen, is the best partially because it feels like a seperate film and isn't mired up in the increasingly annoying "main" stories. The acting is all fine, but the characters tend to be either unsympathetic, unintelligent or both. The film's title and ham-fisted message-mongering imply some grand statement about how much worldwide trouble is caused by miscommunication, but in the actual onscreen action most of the trouble is caused by stupidity: "Hey, let's shoot a rifle at a bus for target practice!" "I know, let's illegally cross the US/Mexican border with two of the whitest tots in all of LA in the back seat and the most overwhelmingly shifty, unreliable relative at the party at the wheel hammered."
Innaritu's heart is in the right place, and his skill is not in doubt. But his message is simultaneously confused and heavy-handed: Eventually it seems as though the film is holding it's audience down, slapping it back-and-forth across the face but without any clear idea of what result it hopes to produce. If I had to re-rate it, it would recieve a 5/10, at best.