Thinking critically -- which was Carl's field, after all -- yields the obvious point that this is emotionally manipulative. I happened to see this comment near the top which kinda says it all: "I actually felt like crying after it was over but I don't know why" (emphasis added). Well, because it's easy to elicit that reaction with music, dramatic shots of the sky, vague statements about the future of humanity... (When I watched The West Wing they'd try this trick nearly every episode, though much more clumsily! It's perhaps telling that one of the only times it worked was when Sam talked about space travel.)
I don't mean to be too cynical about it; I enjoyed the video. I mean, I'm not made of stone. But on one level it's about Carl Sagan, and on another it's about the powerful -- but very vague! -- sense of sublimity that you can induce in people if you phrase something poetically but omit any details. Musicians obviously trade on this all the time, and so do TV shows like Cosmos.
I liked Carl Sagan, and I don't doubt his sincerity or the sincerity of the person who made the video. I also don't want to come off as frowning on works of popular science, which are valuable in themselves (no one can be an expert on everything), and also lead a few people to investigate further. I guess I just like my sublime feelings to be based on something more substantial, not that you can't have your sublime-feelings "candy" too.
It's a bit weird that people are still so easy to manipulate, considering how accustomed we are to all these tricks, the swelling music, the dramatic voiceover, etc. What's, uh... what's up with that?
K, bed now.