First off this is my first review so go easy on me! Secondly i'm not pretending to be an expert I just love films!
Ok on to the film! My personal belief is that this film is one of the best to come out of the year, it can be watched by anyone and you can enjoy it on any level whether just for the spectical and the emotional journey or for the subtext meanings. For me the thing that separates this from other films is the implications and the way it describes religion. In the film, Pi tells two stories, one where Pi survives on a life boat with a wounded Zebra, a vicious hyena, an oranutan (lovingly named orange juice) and of course the 300 pound tiger. The other version of the story (the one he tells to the men from the shipping company) contains the same characters but in human form; where the orangutan is Pi's mother, the zebra is a sailor with a broken leg, the hyena is a brutal calculating chef and the tiger's actions are that of Pi (I'll come back to the tiger).
The important thing to take from the film is that you can't disprove either of the stories as Pi is the only source. Therefore at the end of the film when the reporter (who is the voice of the audience) is asked which story he prefers, his choice remains a belief as there is no right or wrong answer. This is the exact same case as religion. There is no proof that there is definately a God in the same way that there is no way to disprove the exsistance of God.
If you take away nothing else from leaving the cinema take away this!
Now for the countless metaphors you can read into the film begining with the tiger. Lets start with the facts; tigers are very powerful creatures, this power is amplified when Pi is forced off the lifeboat and is forced to make a raft; the tiger keeps Pi alive, he tells us this near the end of the film; (even when he is doing things which may seem to be to kill Pi, he is keeping Pi alive); when Pi and the tiger first meet the tiger is caged by his atheist father and an example is brought forward to disprove the emotional connection between Pi and the tiger; finally the tiger never shows any feelings towards Pi (if any exsist) even after their struggle and everthing they have been through the tiger never looks back before he walks away into the jungle.
All of these properties we find in the tiger, are also present in the definition of God. Like the tiger; he holds great power; he is said to follow a plan and therefore work for the greater good of mankind, even through natural disasters good can still come; in an attempt to disprove the love God is supposed to have for mankind athiests will look to examples which disprove this as was in the case of the goat being killed by the tiger. Then there is the idea that as God protects us in ways we may not understand at the time and needs no gratitude or reward for his actions; which is mirrored in the tiger never showing emotions towards Pi.
The cinematography in this film is fantastic which enhances the appeal to a younger audience. This is combined with the subtext and morals which will leave you thinking long after you leave the cinema. Overall I can not fault this film, not even the acting abilities of the tiger.