Having watched the film (which opened a few weeks ago in Hong Kong), and read the book, I have to say something about the horrible job they have done of adapting this children's classic for the cinema.
In the book, the story starts (as it should) with the Pevensie children. They are on a railway station somewhere in the countryside, when they are suddenly whisked off to Narnia. Later they are told the story of Prince Caspian and why he has summoned them back to Narnia.
The film, on the other hand, starts with Prince Caspian escaping from the castle, and although a rather cursory attempt is made to explain the story, the main focus is on excitement. And action. Then Caspian finds the horn and immediately summons the children (something that takes much longer and is given far greater consideration in the book).
In the film version the children are at Strand underground station in Central London when the call comes. Presumably they did this because it helps to make it clear that the story is taking place during World War II, but it also enabled them to add two unnecessary plot points - Peter Pevensie being caught up in a fight, and his sister Susan fending off an unwelcome admirer. These two themes are developed further as the film goes on, with Peter and Susan both falling victim to the screenwriters' attempts to "modernise" the story.
Then there's the way that the Telmarines are given a vaguely Spanish accent just to make it clear that they are the bad guys. So much easier than giving us the 'back story' that is in the novel, and typical of the unimaginative way that this has been put together.
Some people seem to think that the basic narrative structure of the book would not have translated well to film. I disagree, and in fact I think it would have made a lot more sense if they had left it alone - though I suppose we'd still have had the inevitable CGI and extended battle scenes.
Maybe they'll find a decent director for the next one.