I grew up listening to Michael Jackson and have enjoyed many Cirque shows in Vegas and elsewhere, so One should've been right up my alley. While I enjoyed the show, I definitely felt it was lacking and not nearly as good other Cirque shows or the Cirque-like Le Reve (at the Wynn).
The staging and projections were well done and there's not really a bad seat in the whole theater. The storyline - a handful of kids who obtain different pieces of MJ's clothing and then gaining confidence and power - is pretty weak. Worse yet is that there was very little of the usual Cirque acrobatics. While I was happy to see both the leads and background actors dancing at times it seemed more like watching a Janet Jackson Rhythm Nation concert than a Cirque show. There just wasn't enough of the jumping, gymnastics-style stunts you're used to seeing with Cirque.
Moreover, the balance of the song-selection was way off. There was just too much time spent on some of MJ's lesser known (or lesser loved) music, and not enough time spent on his best work. Some classics like Rock With You, the Girl is Mine, and P.Y.T. just weren't even played.