As an old fan of the Splinter Cell series, this game disappoints. Has the potential to be great, but ultimately fails.
I assume this is Ubisoft's way of making the game more accessible to wider audiences, but ultimately this makes the game a whole lot easier and much more less punishable for not being stealthy. Even Realistic difficulty is easy for most gamers.
The stealth aspect of the game is nearly gone, you can literally just run and shoot throughout most levels. The fact that they added an AK47 to your gun inventory just reinforces this theory. There are many guns which are not stealthy or "spy" efficient.
Story 8.5/10:
The story is is my biggest problem with this game. Why did Ubisoft decide to turn Sam into a rogue agent is beyond me. I was a lot happier with the old spy Sam. What the story does right is keeping you at the edge of your seat by the many plot twists and many "whoas!" and "darn!" through the story. The story is very good but I would rather they went back to being a spy taking out the bad guys.
Graphics 7.5/10:
Artistically speaking they're great, the developers went to great efforts to put as much detail as possible in most of the levels. Technically speaking they're not that great, the Unreal engine on which they worked on is either not up to date or not appropriate for this game. There are many "jaggies" throughout the game and many of the textures are bland, specially some of the character models. The game is not capable of handling great graphics and leaves a lot to be wished for.
Gameplay: 6/10
This is the game's biggest fault. They completely changed the whole splinter cell formula and got rid of the many stealth moves and added a lot of aggressive elements into the game. Many of Sam's moves are gone. No longer can you split-jump into a tight corridor, no longer can you pick locked doors and many other similar things that made Sam Fisher feel slick.
Completely gone are also your trademark night vision goggles and your thermal goggles. Instead you are given a pair of "sonar" goggles. These goggles wouldn't have been so bad if they didn't disrupt the signal whenever you move. You have to be completely still when using these goggles otherwise you can't see anything. What is good about them is that they allow you to see through most walls but they're a far cry from the original goggles.
The mark and execute system is excellent but the problem is that encourages you to kill every enemy you see further reducing the fact that this is suppose to be a stealth game. Many times you can literally shoot through walls should you start your execution and an enemy goes behind a wall. It does add a lot of the cool factor to the game but ultimately doesn't fit in the game.
Expect to play the majority of this game in black and white. The game goes into black and white whenever you are hidden from the enemy. The problem is that you want to be hidden from the enemy at all times and therefore most of the time you'll be seeing black and white. This is a bad choice from the part of the developers.
Multiplayer 7/10:
Another bad aspect of Conviction it's its lack of the classic Spy vs Mercs multiplayer, it is now replaced by Hunter, Last Stand and Face Off. Both of which can only be played with only 2 players at a time so don't expect to invite 5 of your friends to your match. While the gameplay modes in Conviction are not bad they are certainly nowhere near as good as Spies vs Mercs.
The online co-op is great however. It is reminiscent of Chaos Theory's online co-op. It is basically a parallel story to the single player story except you can play it with another friend.
Overall 7/10
Splinter Cell Conviction is an enjoyable game but not as great as it could be. It should be played by both newcomers and old fans of Splinter Cell. Newcomers will find it to be an excellent game if they'd never played neither one of the first three while old fans (like me) will find it difficult to justify the many changes that the game has gone trough.