What Leonard said (because I meant to mention the score in my post and forgot)

From Leonard Maltin's Movie Crazy:

Up celebrates life as the greatest adventure of all, whether you’re a young boy just starting out or an old man. It paints its unpredictable story on a broad canvas with engaging characters, wonderful visual ideas, perfect voice work (by Ed Asner and company) and the attention to detail that defines a Pixar movie. I’m also very fond of the character design, which is based on the idea of caricature rather than a replication of reality: one more reason Up is such a pleasure to watch. It’s also a joy to listen to, thanks to Michael Giacchino’s evocative score.