Our family is pretty knowledgeable about global warming and we were not in a hurry to go see the movie. A friend strongly encouraged us to go see the movie as soon as possible. We saw it tonight. I think that it is a brilliantly designed and executed documentary. It is designed to rouse Americans into action, yet it is not another propaganda piece. It presents a rational argument based on good scientific evidence, ethics based on shared values and opportunities for practical action. If you are a well-informed geek like me, you may quibble with a few details, but the thrust of the argument is sound and the import is huge.
If you are an American and haven't seen it, I urge you, as my friend urged us, to go see it ASAP, while it is in theaters and you are in a position to then urge your friends and family to see it. If you are not an American you will probably want to see it anyway to better understand what is going on in this seemingly benighted country.