To begin with the weaknesses - the film is meant to be three interwoven stories. The interweaving is the least compelling bit of it - the characters do appear in each other's stories, but in a highly coincidental, and not particularly interesting fashion. Secondly, the fact is, the movie isn't really that interested in two of the stories - they're really just kind of there, it seems, to beef up the primary one, namely, the story of a woman named Theresa Poh Lin Chan, whose autobiography provided the material.
Theresa is indeed a fascinating individual. At the age of 10, she became blind and deaf. Yet, she somehow managed to learn English - this completely blows my mind - and even to SPEAK it. The portion of the film dealing with her is ostensibly about her friendship with a lonely widower, but really, it's mostly about her. And she is really interesting. Curiously enough, she spends a lot of time talking about how miserable her life has been. But she's also sort of resigned to it, and puts her faith in God. This may sound uninteresting, but when you watch her, there really is something magnetic and tremendously inspiring about her. The movie is almost worth renting just to see her.
The other somewhat interesting aspect is the narrative mode of the film. In that a lot of the story is conveyed non-verbally, through text messages and internet chats, or a letter that one character is trying to write. In fact, most of the speech in the movie is Theresa's. But there are also a lot of shots of people speaking to her, namely, signing into her hand. There's something really neat about the way the film propels itself through all these various modes of communication. It makes me think about realism and storytelling, and what the most appropriate form of a realistic story would seem to be.
Ultimately though - it's not that compelling a movie, mostly because the first two stories are basically tired cliches. So there you have it.