Got this from Amazon a few days ago, and I can tell you its an excellent game.
One of the things I think that makes this game so great is that it wont let you go through it just getting your shotgun or machine gun out and blasting away.
The game forces you to be clever, intelligent and fast with your decision making.
An example is when you walk into a room and theres three 'splicers' (usual enemies in the game). They spot you and start running towards you. The first few times your put in this situation you usually react be electrifying one and trying to deal with the other two. You'll find that you wont survive that way.
Instead, you must use the environment or other 'plasmids' to get through such as 'enrage' which causes the target to simply go mad and start attacking whatever is around it. So then you've got two splicers fighting each other and the other one is running towards you. Sometimes there may be oil on the floor so you would use 'incinerate' to light them up. Quick mop around with the shotgun and, hey, three dead splicers.
I seemed to keep dieing and failing when trying to defeat the 'Big Daddies' (the ones on the cover) in this way, but, like I said, you must be clever and hack some security bots around the area so when you do attack a Big Daddy, then you've got some back-up and distractions around you whilst your pummeling him with grenades. Its great fun - once you get the hang of it.
The game, ofcourse, has amazing visuals and the sound is brilliant and almost life-like in how theres never silence in this crazy world of Rapture - always water seeping through somewhere or some unexplained explosion in the distance.
Another interesting aspect of the game is that it really feels like your part of this deep narrative of Rapture. The game almost offers you to be sympathetic to the people of Rapture, or treat them like strange, evil things that never had a life anyway. This 'choice' is almost directly offered to you through whether to 'harvest' or 'rescure' the Little Sisters around the game.
I could go on and on about the game, but I would just recommend anyone to give it a go and see what you think - you wont be disappointed.
I'll probably just borrow my mates copy sometime 
