Whoever created these are freaking brilliant. Although this one caters to a slightly older group (I'd say preteen, 8th grader ish) there is something about the way that they lay the cognitive psychology behind it that just amazes me.
(minor spoilers, but not really if you have watched the first one)The second movie elevates the core memory idea into sense of self, and while I won't ruin it, it is really incredible. It's also so incredibly relatable, even with the complex emotions. The way they portray each one is so on point, and lead to an amazing discussion on the various ride home with my almost 7 year old about how every emotion is inside of you, and has a place. I also found it amazing that for this one there were just as many preteens and teenagers that were probably older children when inside out originally came out as adults with their kids.
This franchise really feels like if they do it right, it could be this generations Toy Story, and I hope it does what Toy story missed with the later movies, and they make movies tracking this generation. Just think how amazing Toy Story 4 would have been if they somehow had it be centered around Andy's kid or something like that. Bonnie was a great in between, but that would have been really special. Anyway, go see it. It's worth it.
Also, make sure to check out the credits scene, and the post credits scene. Most left before the second one, and although short, totally worth it.