It's one of those films you come out of smiling a wide happy smile - it's so delicate and subtly funny (alright, it does feature a lavatory, but none of the "standard" toilet humor), it's also kind to characters and makes its point(s) in a sly, unobtrusive manner.
It's a celebration of human values over the way of the samurai, especially as it has been presented in Japanese and Western popular culture in the past few decades. A joy to watch visually, too. I thought it might be Koreeda-san's best film so far, although some viewers may find it a bit more conventional/Westernized than, say, Nobody Knows or Maboroshi (which is not at all bad).
I will deliberately leave it at that, to avoid revealing any of the plot, which often overturns expectations.
It was the second film out of 17 I saw at the Toronto International Film Festival, and it still remains a highlight for me.