There are so many ways to describe the quality of this game and the fun you'll have playing it.
If being engrossed into a game's story is not your thing then pass this game up. I seriously never have witnessed people watching me play a game and be so into it themselves. Not only am I immersed into the situation unfolding on-screen, so is everyone around me and they aren't even playing it! I want to turn the game off for a break but they say, "come on ONE more chapter!", chapter after chapter.. That should give you insight into how great this story actually is. It does have it's plot holes but the story is still nothing short of spectacular.
The voice acting is very good but sometimes the characters break their North/East-American accent and sound French(how many mile Jaden?). However this really doesn't take away from the excellent voice acting and the amazing score.
The graphics are simply a 9/10, not really an explanation on how great they are, look at the gameplay yourself.
I would also like to mention how well this game plays on the Playstation Move. At first I found it hard to play on the top skill level because you need to shift controller positions and press seemingly unreachable buttons very quickly. Once you get used to the controller(s) it's a bit easier, but the lower level works fine(almost better), and you don't feel left out on the action. When playing with the Move most motions feel natural and you should have no problem. After playing this with the Move I can't see myself playing Heavy Rain with the regular controller. This game almost seems like it was specifically made for the Move.
In closing, don't expect crazy video game shootouts, but expect scenes that are much more intense than that...