I just played through the main mode of the game and it completely fell flat for me.
I'll get the good out of the way, visually the game is spectacular although I wish there was a little more variety to the environments and choreography. The falling out of a window sequence as shown in the trailer was a neat visual metaphor but it happens at the beginning of the game and there isn't much more like it throughout the rest of the game. That is more or less the only good thing I have to say about the game.
Now for the mediocre, I played the game on a controller and everything felt so floaty and imprecise that the game became frustrating. Along with the sloppy controls (which probably are a lot better on an iPad or something) the gameplay itself is dull. The game mechanics aren't all that bad but at no point did I feel like what I was doing on the screen interacted meaningfully with the music, I never felt any of the flow that makes rhythm games so entrancing. Finally, the music was a letdown. The majority of the levels are 1-2 minutes and are just a repetitive beat with little in the way of melody and no lyrics or variety. After each level you're briefly kicked back to a menu so any momentum that the filler levels might have contributed to the game as a whole is lost (although post-game there is an album select mode that plays straight through without kicking you to the menu, which would be nice if the game was worth playing again). There are a few more fleshed out songs that play during what amount to boss levels, unfortunately the best of these songs is in the trailer and some of them are as forgettable as the filler levels.
For me, two moments really stood out in the game, the first was the level with the song from the trailer because the song was good, and the second was the closest the game came to being engaging, a sequence where the music snaps between two different realities ala Titanfall 2. Overall, the game was a kind of cool audiovisual experience but it failed as a rhythm game. It is easy to see how much effort went into the game but it's hard not to be disappointed that so much of the finished product was forgettable.