If you've seen Amelie and were put off by Audrey Tautou's slightly saccharine portrayal of a wide-eyed innocent, then you might also be put off watching this film. That would be a great shame, because it's a very fine one. For a start, it's really not a sentimental film, despite the title. It opens with a horrific scene of the trenches in World War One, and half a torso hanging off a blasted skeleton of a tree like a rag.
A small piece of ornithological geekery: albatrosses are significant to the plot, and at one point, Mathilde and Manech are at the top of a lighthouse and see a big white bird, referring to it as an 'albatross'. It was actually a gannet (Sula bassana), not an albatross, so either no-one on the film knew the difference, or they did but couldn't get any film of albatrosses. Alternatively, the translation for gannet might be confusing (my French vocab doesn't quite run that far).