My only disconnect with the trailer is that I always read Pi as being younger than he appears to be in the film.
Pi is between 14-16 in the book, but given Hollywood's propensity to cast older actors in roles like this, we shouldn't be surprised. In the Hunger Games, Jennifer Lawrence is 21 but Katniss is supposed to be 16 as well.
I don't read novels, strictly a non-fiction guy, but I love science fiction/fantasy films. This looks good although I am not quite sure what it is about.
Essentially, they lay it all out in the trailer without giving away too many plot details: Pi is a young Indian boy who is moving to Canada with his family (who own a zoo) aboard a Japanese freighter. There is a terrible shipwreck, and everyone aboard dies. Pi is able to get into a lifeboat, but a few of the zoo animals also make it into the lifeboat, including a Bengal tiger. The story is about Pi's journey across the Pacific. As with most Fantasy, the journey is an adventure.