I watched this last week, so I shall try to remember what I loved about it.
I think this was one of Johnny Depp's best performances (well, of those I've seen which is probably just over half of his films). It's more of a typical-Hollywood-leading-man role than many of his other characters, and he does it so darn well. One of Depp's great strengths, I think, is his ability to move his character through time, to portray a long timeline of a character's life as they age - keeping the essence of the character but changing in those subtle and varied ways that people do as they age. And if you try to ignore the not-so spectacular old-man makeup, the last part, as an older George Jung is prison, is beautiful.
Penelope Cruz impressed me too. It's not easy to play someone who's always stoned with resorting to boring cliches, but she did it well. I really liked her character but I didn't feel sorry for her, which is good I think because it menas they just told the story as it is, without trying to impose feelings on the audience.
All the supporting cast members were great, the characters all played their part and all meant something to the story as well as emotionally.
Anyway, yes, I loved it.
Plus: Johnny with blonde hair. What is there not to like?