For mystery game lovers, this one is middle-of the road - entertaining, but not a serious sleuthing challenge.
The puzzles are entertaining, and decently difficult, although unfortunately not particularly relevant to the story line. For those who don't enjoy puzzles, there's an option to skip them. The puzzles are combined with a variety of other challenges that keep things interesting. Your viewpoint changes in different parts of the story, and at one point you get to see the world through the eyes of a dog!
Like most mystery games, the focus is on the story line, so there is little side action, and as a result the game is quite short. I completed it in about 20 hours, taking my time.
The game has only one save slot, and does not auto-save. Although this is not a game-killer, I would have appreciated the ability to re-play some scenes different ways, to see all of the possible character reactions.
Now for the bad. The game is completely linear. In order to complete a scene and move on to the next, you have to find every key clue. Several are in un-obvious places, and you have to put the cursor over them precisely for them to pop up. On a PC with a mouse, that may be easy, but on the PS3 it's definitely not. To make matters worse, the vertical and horizontal controls can only be inverted together. Since I'm used to playing with normal X control and inverted Y, I found it annoyingly difficult.
Like many players, I have a threshold where I give up and check the walk-through. On a good game, this usually results in a head-smack: "why didn't I think of that?". In this game, the times I got blocked were mostly on missing clues, and the head-smack happened only about half the time.
None of the "deduction" is subtle. It's either very straightforward, or so random that you have resort to trial and error. One illogical chain was so long that I gave up and checked the walk-through.
My overall reaction is that, while I enjoyed the game, I have a hard time comparing it favourably in value (at $40 retail) to things like the most popular RPG games, which are good for 100+ hours if you do the side quests, and cost only $60-$70.