Actually, there was already such game that already tried to shape the content and the story, to a varying degree, depending on your actions, even going as far as asking you a series of questions with a psychiatrist and it was a game made for the Wii (eventually released for the PS2 and PSP), it was Silent Hill: Shattered Memories.
I know, first hand, that the game doesn't feature many combat sequences (like any at all) and even the scares aren't that scary when you discover that you only need to shit your pants when the environment starts to freeze (literally), but I still liked this game for other reasons.
The game was supposed to shape the story, it's characters personallity and some subtle details in the environment to be your own experience, at the beginning, the game opens up with a doctor asking you a series of questions and even after that initial questionaire, the game keeps showing you the doctor now and then, asking you more details about your personality, many people would think that the questionaire would be only limited to the doctor, but the game keeps analyzing your actions ingame.
How much do you search the environment for clues or items?, did you look at that girl's breast when she was talking to you?, do you turn around quickly when you hear strange noises?, those and other details are being analized by the game in real time, without you knowing.
Sadly, the game has it's limits, but it's certainly interesting to see how much the game changes when different people plays it, I know I tried, I invited my cousin to play the game and a lot of different things happened to him, compared to my playthrough.