I think that technically the full name of this game is Call of Duty 6: Modern Warfare 2 or I may just be confused by some rebranding sleight of hand but who cares? The game sold 50 hoojilion copies in its first day, and for an understandable reason: developer Infinity Ward's last entry in this series was really, really good and Modern Warfare 2 is too.
It's a first person shooter set in what feels like a military setting that's just futuristic enough to feature weapons of war that are amazing but not quite at the science fiction level. The plot is like the drunken love baby of Tom Clancey and Michael Bay and is even more over the top than the first game. All hell breaks loose as various worst case scenarios from a war with old school Superrussia blow up in your face, plus there's big explosions, gravity defying snowmobiles, sneaky sniper assassinations, nasty urban warfare in a surprising setting, and the an inverted version of the shower shootout scene from The Rock. In general, the worst thing about the game is Infinity Ward's inability to tell a coherent storyline, as your hopscotching from one cast of character to another is often befuddling and the motivations and even actions of the major characters go without sufficient explanation. All this because Infinit Ward is doggedly exchews cut scenes and thus delivers its storytelling through rapid-fire in-game dialog and little sequences of images during the loading screens between levels. It took me two playthroughs to get a grip on what the heck was even going on, and even still there are several things that remain mysteries to me.
You know what, though? That's my only complaint about the game. That's IT. The gameplay itself and even the big picture are just fantastic, with one magnificent set piece after another with absolutely no fat or filler. There's nothing about the game that's inappropriately paced and nothing gets a chance to feel old before being replaced by something of equal but different awesomeness. There are some rumblings out there on the Internet about how the single player game is only about 5 hours long, but it's the best 5 hours of gameplay I've had in a LONG time. I definitely got my money's worth, especially since it's good enough to go back into and play again.
And even once you do beat the single player game, Modern Warfare 2 has an incredible multiplayer to go with it. You can play "Special Ops" mode in co-op with a friend, which mostly takes segments of the single player game and challenges you to complete them under new circumstances, like killing a certain number of enemies or holding off wave after wave of attackers. It's a lot like the challenge rooms from Batman: Arkham Asylum, except you can play them co-op with a friend.
But of course, most people going online with this game are doing it for the competitive multiplayer, and while I haven't played that much of it I can tell you that so far it seems really robust and a lot of fun. The carrot on a stick mechanic of leveling up your multiplayer character and unlocking new weapons and abilities is still there, and it gives you a great sense of momentum and "just one more unlock..." motivation to play game after game. Even if you lose a given match, you feel like you're accomplishing something. As you proceed you can select new buildouts with different weapons and attachments, plus you can select "perks" that give you special advantages on the battlefield, like the ability to hide from thermal scopes or faster running speed. The game also features "kill streaks" where you can unlock REALLY powerful abilities like calling in heavily armed helicopters or missile strikes if you can score a certain number of kills without dying. Fun stuff, and I don't think I'm going out on a limb in saying that this is where the longevity of the game will be.