I enjoyed this but didn't love it as much as some people have, for a number of small reasons that aren't worth going into. So much depends on endings, and this one has a smart ending, but I felt like they didn't quite nail it. So I recommend it to fans of animated movies and give it a B+. Stick around for the credits to see a little of the making-of.
While I quibble, I understand why the people who rave about it raved about it. It's an impressive accomplishment. If I hadn't seen the rave reviews, I might be writing one now—it's possible I was hoping for a little too much. There must be a term for being a bit disappointed by something you would've enjoyed more if your hopes hadn't been raised too high. If my quibbles make you go and think it's better than I've suggested, I'll both understand and be a little pleased.