
I think the reason that Persuasion is not oftener adapted for film and television (unlike Austen's other works, which have all been made into tv mini-series, films, even choose-your-own-adventure books, and a zombie parody) is because the main character is old (27). Because of her advanced years, it is believed that Anne Elliot is matronly, disinterested in romance, and predisposed to take care of every person around her, as if caring for her friends and relatives could replace the man-shaped whole in her heart.
Anne Elliot is actually required to take care of her friends and relatives because generally they are socially stunted, inconsiderate boobs. Her father for instance, is enmired in debt and doesn't have any plans to get out, her hypochondriac younger sister doesn't know how to manage the hellions she's birthed, and her friends are social meddlers and try to persuade her to do things that aren't in her best interest.
Concerning the above, the movie is very faithful to the book. The sets and costumes are more suited to the regency and less to the romance of the story, ie they are historically accurate rather than sanitized with bright lighting and lavish sets. The characters are not all beautiful, and the lesser characters do not exist to make the lovers more loveable. Another really strong feature of this film is the delicacy of Amanda Root's expressions. The visual cues in this movie clarify the Georgian manners that often confuse modern readers of Austen's books.
Characterization is less developed in the movie, and so, I would recommend reading the book (
purchase here) to get the full drama of it. You may want to see the movie just so you can imagine a beturbaned Lady Russell played by a committed Susan Fleetwood as you read.