GET THIS GAME!
What? You need more of a reason than just me saying so? Ok... I'll bite
OH, one word of warning - there is some TV grade language in it as well as a few J-C exclimations (that in my opinion could have been changed or left out all together)... just to make you aware of this. (also note = this is not an offical review, just some ramblings from a fan).
Ubi made the mistake of releasing this in the midst of the pre-Christmas rush and it got lost in it.... and the good side of that is you can now get this gem for about $20 US.
Beyond Good and Evil is mostly an action/adventure game (much like Zelda), in fact this might be the closest thing right now on the XBox that you're going to get to Zelda (Azurak runs a close 2nd, but lacks the player/NPC interactivity that makes Zelda great).
One of the other things that I love about this game is that it has a bit of Pokemon Snap in it (i.e. taking pictures of local wildlife, sometimes even requireing you to be creative with your surroundings to get the shot). As a photojournalist the main character uses her camera quite a bit, and this photo-collection is one of the main sources of money for you in the game.
The game has elements of stealth in it (though not nearly as complicated as something like Splinter Cell or MGS2). What's amazing there is how well the game handles the character in these situations.... the character automatically hugs walls when standing next to them, tip-toes around even when you're not moving along at a crouch so as not to be seen, etc.
Like most action adventure games it's as much an exercise in collecting stuff as well, in this case pearls are very important (as they are used for purchaceing some upgrades).
The game was never tiring or mundane (though it does make the game a tad shorter than I would have likes, but much more might have put too much of doing the same thing over and over again into the game).
The camera was excellent.. in several ways. 1st, I almost never had problems with camera angles while playing. This is a common problem for 3rd person perspective games (Mario on the 64, as an example, was terrible most of the time). 2nd, the use of some fixed camera positions and some special effects with speed and motion blur added some really cinematic effects to the gameplay.
In a few places the camera angle starts fixed and follows you part way across the area you're moving, then falls in behind you like it normally is, and all done seemlessly.
In addition in a few places, the beginning of the game being the most obvious, the main character is faced fighting some monsters that have landed, and is having to fight hand-to-hand (so to speak), she destroys one (which releases the child it grabbed) and another one pops up to attack. After a bit the music is playing, the speed of the game slows down (slow motion) and the sound effects become somewhat distant.... much as you might see in a very dramatic battle in a movie (think LOTR, there are a few scenes in there that used this techique).
The game makes clever use of a follower character that often partners with you (and is often times necessary to solve puzzles or to kill enemies).
The game has drama, places that just might make you cry, and places that'll have you laughing out loud (well, I did, but I'm fairly easy to get a laugh out of anyway, so, your milage may vary). Cinematic is the only way to really describe it (yet unlike a game like MGS, you're not faced with too many places where you just sit and watch).
On top of all that, there are some really nice touches to the game world.
1) The game world has day and night, and it doesn't effect much, but it does give a sense of life to the game world. At night in the city, for instance, the windows of the buildings light up, signs are properly lit, etc.... all fading from day to night to day.
2) The digital camera you use identifies items for you at times (for instance, when in one of the outdoor enviornments it'll ID the city, some of the other locations, etc when you point the camera at them). Several of the many items it identifies are the starts in the sky... giving the name of the star and/or it's constelation it's in... a simple touch but still nice (again, giving extra life to the world).
3) The above mentioned stars are also identified in the reflection of them in the water! (how cool is that!)
4) People in the street wander around some, and the crowd changes as you progress through the game.
The only thing that would have made the game better would be if it was longer (maybe they'll do a sequal to it) and I think the photos of the animals are fixed amounts that you earn, it would be nice if they also paid you based on the quality of the photo and allowed you to replace shots when/if you get better ones (much as Snap did).
Now, why are you still sitting there and not out buying it? Hmmm?
Also, shoot any boxes in your way, that always helps. 
