Le Reve is best described as Cirque du Soleil meets synchronized swimming and diving. I really liked this show because it's different from anything you've seen before. I also loved the theater - since it's round with no support beams, there isn't a bad seat in the house and they were able to pull off some pretty cool stunts and surprises with it. I probably spent half of the show wondering how different parts of the "stage" work, however I promise that the acrobatics and special effects are much more interesting.
Definitely would recommend to people coming to Vegas as a top show to see.