I read the book and didn't really like it, so I'll pass.
Tonight I went to
Carnage, the new Roman Polanski film about two bickering upper middle class Manhattan couples. I don't strongly recommend it. The four leads are all normally good actors--John C. Reilly, Jodie Foster, Kate Winslet and Christoph Waltz--but in this case they came off as actor-y and artificial, particularly Jodie Foster, whose character just way seemed over the top. The problem was partly the screenplay, but I felt like if Jodie had dialed it down a little it would have worked better.
Christoph Waltz played an American businessman, and although his mastery of an American accent is a stunning accomplishment his pronunciation and cadence sounded to my ears just a hair short of authentic. I felt the same way, actually, about Michael Sheen's American academic in Midnight in Paris, and wondered why they bothered to make him American; the character would have worked just as well as a Brit. Now I wonder if all the American actors who play British or European characters sound grating to people from those countries.
Two non-American actors who do really great American accents: Hugh Laurie and Christian Bale. Oh, not to mention Heath Ledger!