So I saw the show yesterday and here's my take.
The orchestra is amazing. They all played together perfectly and sounded fantastic. If you're into instruments, broadway music, production, etc..you'll appreciate this show.
The issue with the show is what I think a BUNCH of people aren't realizing is that their not playing hit sing a long songs from the movies. What their playing you won't find on a "Now: Disney edition" cd. I think many people are going in expecting to hear a band play something like Let it Go, Under the Sea, etc while movie clips are playing and people are singing a long. This is not the case. Because of that is why I think many people leave the show. Just at the one showing I watched, I probably saw 30-40 people get up at different times and leave.
The show shows movie clips from different Pixar movies and the orchestra plays matching music to convey the emotion. There's no words (until the very last song of the show when the characters come out). So when they show happy scenes you hear upbeat lively music, when there's depressing scenes you hear mellow sad music.
Characters come out on the stage, the green army men are there prior to the show as comedic relief to pass the time.
If you know you're not going to see something like the Frozen sing-a-long, and you enjoy an orchestra, then you'll enjoy this show.
I recommend showing up 30-45 min early to get a good seat and to be underneath the roof so you have fans. I was running late and showed up 5 min prior so we had to sit in the bleachers. Not a bad seat anywhere view wise, but up closer and under the fans is preferable