American Hustle is a movie with a clever plot mixing fact and fiction, and features equally clever acting that kids fifteen and up will appreciate, along with their parents. The "R" rating seems to be more for the prolific curse words rather than the violence and sex, the elements of these more in line with current PG-13 movies. In keeping with the 70s timeframe and the nature/fallout of ABSCAM (on which the movie is lightly based), there are some ethnic stereotypes not in line with today's inclusive ideals, just FYI.
That said, this is a movie not to be missed, with magnetizing chemistry and performances -- absolutely electric. Although Argo (which won best picture) probably more accurately portrayed its signature events that occurred at roughly the same point in time, American Hustle, for me, was a far more riveting movie -- and I enjoyed Argo, too.