The good: I was pleasantly surprised by how well the film handled the age difference between Bob and Charlotte, focusing more on human connection than romance (ignoring the terrible last scene). The mood was really spot on, with some great cinematography and music.
The bad: The main characters. They're just too shallow. Bob's a terrible husband/father (notice how similar he actually seems to Charlotte's husband), and Charlotte's your classic Ivy-league graduate with a philosophy degree. Neither character really develops much.
The ugly: The borderline racism in the film's portrayal of Japanese culture. It's not so much that things are 'lost in translation'—but that the protagonists fail to even attempt to understand Japan themselves. And that applies more broadly in their lives too.