The great critical and audience success of Toy Story 3 continues Pixar's unprecedented streak of success--in any type of filmmaking, not just animation--leads one to contemplate why this team continues to make good films, let alone landmarks in their field.
What is remarkable, if not miraculous about Pixar, is that they combine (1) cutting edge technology--the raison d'etre for Pixar; (2) top-level animation skill; and (3) straightforward film skills, including editing, camera movement but most especially long and painstaking development of story.
When you think of it, those are the skills that the original Walt Disney organization offered, but they still stumbled on story fairly frequently, and often did not have the money to push technology. And Disney never had a streak of first-rate features in his life like Pixar has.
Everyone is aware of this, especially the rock-solid story construction under the leadership of John Lasseter. But we all seem to forget that Pixar executes first rate animation. Most notable in Toy Story 3 is the Spanish version of Buzz, little Bonnie, and Andy himself. (You would be surprised to look at the first film to see how crudely Andy is animated--he doesn't much very differently from Woody himself.)
Maybe the absolute highlight is the simple and authentic way in which the characters look at each other and hold hands when they believe they are facing their doom. There is not a trace of irony or camp, and audiences are devastated.
Because finally, the heart of animation is characterization by physical representation--the same thing that actors do, except being done by visual artists, via detailed observation, recreation and heightening of expressive movement. Plus, it can be real real funny, too.