I've played through the demo and I'm absolutely sold. It's a very different kind of game, which is to be expected. It plays out in a very cinematic fashion. It's almost like an interactive movie.
Controls take a bit to get used to though. There are plenty of quicktime events and you'll be pressing buttons in certain sequences, repeatedly pressing the same button, shaking the controller, etc. Failure to do so will either cause you to have to redo the sequence or it could result in your character taking a hit.
You press R2 to walk and use the left analog to control the direction of movement. All the other buttons and the right analog are used to perform context sensitive actions, when they show up on screen as an object that can be interacted with.
Dialogue offers branching paths, and it can drastically affect the outcome. In the demo, you play as the private detective and the FBI agent -- each in their own scene. You're digging for info from one of the victims as the PI and depending on your actions, different outcomes occur. For now, the general outcome appears to be the same, but I believe it may have an impact further into the game. In the FBI agent scene, you get to use this evidence finder glove/glasses.
Overall, I'm impressed with the game. The story is very interesting, and the gameplay is quite different from what we're used to nowadays.
The only thing I am worried about in this game is length. So far, we've only seen a handful of scenes. I hope the story is interesting enough and the game turns out to be lengthy or to offer enough different dramatic outcomes to warrant multiple playthroughs.