I was simultaneously horrified and frightened while watching this trailer. Its focus is Tilikum, a male orca in captivity responsible for three deaths. I've only now been reading a bit about the film, but what I've learned so far has really made me think twice about the idea of taking my little boy to Sea World or any facility that derives entertainment from the animals through performance. I can't say that I'm not happy to take A to a zoo or aquarium so that he can see animals that he will never otherwise encounter, but I also know the idea of wild animals in captivity shouldn't be so easy for us to accept.
The Hollywood Reporter's review of Blackfish at Sundance is very informative-definitely a good read if you'd like to hear more about the documentary.