Battlefield: Bad Company. Game mixes beautiful sounds of gunshots from any distance, the farther away, the more faint the sounds will get. Every shot and explosion is heard by EVERYONE, each with their own distinct sound based on different distances apart.
Coupled with the perfect sounds is the excellent storyline, which'll take you through the whole world in many different environments. You'll use many "abstract" weapons which you've probably never heard of, definitely something Call of Duty doesn't have. You'll drive vehicles you've never heard of, or seen, such as the T-Series tanks made by the russians.
Every weapon in the game is absolutely useful, and all can be used to kill anyone should you be good enough with said weapon. There are 5 different 'kits' to choose from, all with their own gear. You purchase weapons through ranking up, and it's actually up to you what you want to get. The game requires heavy teamwork and cooperation to win a map, you really can't rambo here, given that each level is miles long. You want to walk by foot in an open field? Enjoy getting sniped or airstriked! The use of cover is absolutely NEEDED in the game, especially when you choose the Recon kit and decide you want to snipe. The ghillie suit is already hidden enough if you're in the right environment, but if you get next to a tree, or inside a bush, no one's going to find you.
All guns, except the ones with suppressors on them, have muzzle flash. So if you think you're going to be the coolest sniper ever and sit in one spot the whole game shooting at people, think again. They're going to see the direction of the shot every time if they're even paying attention in the slightest.
The storyline takes place with you playing as a new member of B-Company, a Company full of rejects and fu-ckups. As they move along through their missions, which are hilarious due to the humour of the men in the squad, you'll eventually be found chasing after Gold through the entire country.
The singleplayer is excellent, and definitely worth at least 1 more playthrough, and the multiplayer is phenomenal, especially if you have friends.
There are some downsides, however, which impact the multiplayer extremely hard. The Devs decided to use a sort of 'squad' system when playing Multiplayer. Each team has 2 squads. The downside to this, you can't talk to anyone in a different squad, so if your mate gets in a different squad, you're best off waiting 20 minutes for the next game, or just going into a private chat, I find that the latter is the most effective.
Regardless of a couple more little downsides, the game is phenomenal, and I must say, the best for the Xbox 360.