I admit, I was slightly disappointed to begin with. Having played the Demo, which I thought was excellent, I found the first 2 levels infuriating, with enemy soldiers shooting, with perfect accuracy, automatic rifles and making shots that I was struggling to make with my sniper rifle - admittedly I was playing on the hardest version with none of the sniping aides in operation. However, once you get your mindset into "once you make that first shot, you best be prepared to take everyone down" - the game really comes into its own. You must plan your attack; where your most defended position is, and protect it using mines and trip wires; where the enemy congragates in order to plan grenade or dynamite attacks. Once they hear that first shot, the enemy attacks relentlessly.
Other reviewers have complained that the AI is too good - I would argue that with easier AI, that it would simply turn into a shooting range. The AI makes you think about the best time to make the shot - creates a nervousness before setting into motion your plan, and in essence is what makes the game frustrating, yet addictive. There are a few bugs - some of the movement is not fluid, it is incredibly difficult to plan an attack perfectly; you sometimes need to fail in order to understand where the enemy troops move to, in order to plan better. However, graphics, atmosphere and addictabilty are there in abundance. It's not fast - it's the thinking man's game - if COD is the 100m and Battlefield is the marathon, Sniper Elite is an excellent game of chess. Buy it.