Yep, what Steve said above. I agree that the delicate subject was handled very well. I also commented to him as we were leaving that the message was perfect timing considring the whole "green" movement that is so big right now. And I didn't see it as much a love story, as a message story about things could go if we're not careful. I felt that the love story was a very big part of the plot, but I didn't see it marketed as such. If though I did get a kick out of the musical movie/theatre reference.
Although why does everyone keeping forgetting the Pixar film Dinosaur? It's one of my favorites!