I saw the trailer earlier, and I heard that they made the trailer that long because they had a hard time compressing the story down any farther to still get it to be understandable and entice people to watch. And after I sat and watched it, all I could think of was "dafuq did I just watch?" I mean, there were certain parts of it that look interesting, but I have no idea what was going on.
Which is exactly why I suspect the movie will have similar issues.
Knowing nothing about the story beyond this trailer, I'll take a stab at the story: it seems like it's something similar to Specimen Days
, in which three separate short stories are combined into one book with the "same" three characters repeating in them: a boy, a woman and a man. They take on different roles in each story, but the idea is that they're inextricably linked, whether it's their souls passing on after they die and coming back again or karmic connection or whatever you might call it. Cloud Atlas seems like it has a similar we-keep-running-into-each-other element, given it's the same actors repeatedly ending up together in disparate times.
...except for the super-future scenes, which had different characters from all the other settings, which admittedly confuses me. Unless that's simply recognizing that the world's racial layout is likely to be different that far ahead in time, I'm not sure why things get changed there.