Okay, I took part too, despite not having seen the film, which isn't in general release yet. But my take on the discussion was a little more general:
The thing about stereotypes in a comedy is that almost every character starts as one. It gives the filmmaker a set of viewer expectations to violate. The question is where do these characters end up? Are they still stereotypes by the end of the movie?
I didn't get an answer, in part because that comment thread was, at heart, only tangentially about the movie. Today, though, the local paper has an interesting article on the uses of ethnic stereotypes in film. There's the discussion of the current state of the art:
In an ever-more-diverse United States, movies that trade in ethnic humor increasingly aim to give us laughs we don't need to feel guilty about. They often have, or at least claim, a de-stigmatizing effect. They lampoon bigotry, or the prejudices of people who imagine themselves open-minded when they are anything but, turning chauvinism into a punch line.
But the piece that really caught my attention was this:
Nearly all comedies traffic in stereotypes -- it's a quick-and-dirty way of connecting with audiences, giving them something they recognize, exaggerated for humorous effect. In fact, humor often depends upon that context of familiarity.
Vindication! Not that I thought I was wrong, but it's always nice to be agreed with, especially when I'm talking off the cuff. There's nothing quite like generalizing from a small sample and broad impressions and turning out to be onto something.
The article itself goes into much more depth and is worth reading in full, particularly for anyone who wants to write comedy.