This post is going to be short as there is not a laundry list of gripes and complaints that I'd spend paragraph after paragraph cataloging. In fact, this was my favorite movie since last year's "Dark Knight". All though... this movie has less punching and fire. And its probably my favorite Pixar movie since Incredibles (and, Leaguers, I loved Wall-E. This one just pushed all the right buttons).
Pixar's focus on story and character is generally much better than most movies in general, and is light years better than most all-ages entertainment. And the impetus for the story here is not what you'd normally sell as a kid's movie, just as I'm not sure kids would really get their heads around the existential dilemma of Bob Parr in "The Incredibles" that leads him to re-don the spandex.
The characters are very well defined, and the script features none of the relentless mugging that's mistaken for jokes in the average Dreamworks project that's the legacy of Robin Williams' "Genie" and trying to recapture the lightning in a bottle that was the first Shrek movie. Instead, the humor (and tears) come straight from the story and characters.

Our protagonists. I really liked that bird.
The animation is fantastic, and I guess you can see this thing in 3D in the right theaters (we didn't miss it). But the character design, etc... all feels spot on, as do the various set pieces.
I would forewarn parents of kids under 7 or 8 that we had a scared kiddo sitting behind us. There's nothing too threatening popping out at the heroes, but I sort of think that because the movie does a good job of wrapping you up in the proceedings that when danger does occur, the kids may get a little more spooked than normal. There is a little more "life and limb" sort of danger than in Wall-E.
Two of our protagonists are not human. There's a huge bird whose name is actually a punchline, so I don't want to give it away.
And, of course, there's Doug the Dog.

I have just met you, and I love you!
For all the tear-jerking and hilarious moments in the movie, the parts with Doug were my favorite. (If you like dogs, this is really a good movie for you.) But it was also a little sad, given our year, only because Doug was, more or less, Melbotis.
I was surprised by developed Karl's storyline was, and how gently Russell's storyline was conveyed, when both could have been standard kid's faire, heavy-handed stuff.
There are some great action sequences, and I know I was never bored, and neither did the kids ever seem like they were growing impatient (just wait for the little planes to show up).
Anyhow, I don't have much else to say, other than that I hope you Leaguers see it, and hope you enjoy it as much as I did. Its also great to know that Pixar's collection of talent is so deep. While I love Brad Bird and the rest, these guys really knocked it out of the park.