Um, WOWWWW...
I've only seen Zumanity before O but I think O trumps all the other Cirque du Soleil shows. I still want to watch KA, Love, and Mystere but I'm not sure if they can top O. We will see.
We missed the first 10 minutes of the show because my friends were late but it was still worth the $168.50 I paid for lower orchestra tickets. If you're late, they hold you at the doors until there is a pause in the show, then they escort you to your seats so DON'T BE LATE...they aren't Asian so they start right on time.
All in all, if you're looking for a Cirque Du Soleil show to see...you HAVE to throw down some $$ to watch O! You won't regret it. Oh and bring a light jacket too -- when the water starts splashing around, the temperature in the theatre drops so you might get a bit cold if you're sitting there in shorts and a tank top.