Despite loving Austen, I actually never managed to finish Mansfield Park because I got bogged down in the bit about putting on the play. But I just saw a movie version (er, it had James Purefoy and Lindsay Duncan in it [and you can tell by the actors I recognize that I'm currently watching Rome, can't you?] - aha, it was the 1999 version) and I enjoyed it a lot. I agree that Fanny is a strong character, who holds to her principles even when everyone around her (and the general situation) would be urging her to give in.