"I remember a lot of passionate discourse at the other forum about how vile some thought Raging Bull was, that brilliant performance or no, the subject (and subject matter) didn't warrant glorifying the brute known as Jake La Motta."
Well, their contention was that what Scorsese does with the story and character of La Motta wasn't very interesting.
I tend to disagree. As I wrote in an article (http://groups.yahoo.com/group/noelmoviereviews/message/149) once, as straight biography the movie tells you nothing, but if you see it as a story told by La Motta, what he tells and what he leaves out, I think it's something far more. For one, all the violence and ugliness he leaves in, which is in keeping with the his masochistic nature, his seemingly unending need to expiate himself for some unnamed sin (sort of like Gibson, only with more sensitivity); in a way, I think the unrelenting brutality onscreen is La Motta's way of beating himself up all over again.
He does not, however, give us a definitive explanation for exactly what sins he's expiating. That remains unexplained, and that's what makes the film so fascinating for me. It's essentially a Passion Play with a mystery at its core--again, like Gibson's Passion of the Christ, only told with imagination and a real sense of spirituality.
David E. wrote an interesting essay on Raging Bull for Criterion by the way. Worth looking at.