the game is poor in my point of view
Over view-
Individual design is drab and non-remarkable which leads to difficulty into on the fly IFF. you will often have great difficulty making out Friend from foe in heated fire fights to the point that often you'll end up unloading rounds all to often into friendlies through out the single player campaign. of course, no worries on this though. non-essencial friendlies are effectively red-shirts and will always reinforce you, even in maps where you are TOTALLY CUT OFF, and essencial friendlies can take a 120mm Tank cannon blast to the face so a few rounds is of no major consquence for the most part.
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mechanics are bland with the 'hide in corner-suck thumb-regain health!' mechanic working in full effect. however, this often works at odds with the pescribed pace the game tries to impose on you. the game is built to be fast pace with you jumping from cover to cover, squeezing off a few shots and displacing... but with the 'suck your thumb' mechanic in place you'll often find yourself pinned down many a time.
bullet dynamics are linear with no degredation (in other words unrealistic) having no trajectory or travel time which is only off-set by having bullets do crap damage. (again unrealistic) you'll often find yourself putting half a magazine of high caliber assault rifle into individuals just to put them down only to have them scramble back to their feet and continue fighting. ontop of this guns are horribly inaccurate by default in an attempt to force players to 'aim down the sites!'
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level design is generally linear as it usually has to be in order to support the quick pace it wants you to pull. because of this you'll often not be able to see some wonderfully rendered areas, expertly done back drops, and beautiful effects which fill the game from time to time.
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the story is bland and for the most part, and sevearly lacking in most all parts.... there are so many loose ends and pointless detours in the story that it gets very hard to follow at times. several points in the game often feel like detours designed purely to 'show off explosions' even though they serve no acctual real purpouse in the story... ontop of this you are often left in the dark about objectives, reasons, or consequences from actions you did in previous missions.
if you think i am wrong...
Who is Raptor? (we presume he is POTUS but we are never told that... as far as we know he could be corpate leader of major sock knitting company)
Who is the HVT in arcadia?
How did the OpFors Deploy BTRs, BMPs, and Attack Helicopters in DC??... such heavy equipment requires deep water ports for off loading and can not be paradropped in.
how did the troopers deployed in Iraq get to DC? ... infact What in the hell where they doing in DC At all??
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and to add insult to injury, you can finish the single player in a single sitting for the most part. it is painfully short... even for a CoD Game.
if you can over look all of this, the game is punctuated by very pretty levels which are often subsquently destroyed through heavy combat. explosions are pretty, and the game does have a few 'Woo! epic!' moments from time to time.
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multiplayer...
PC version gets the short end of the stick on this one.
the lack of dedicated servers just sucks for the PC Player. the average PC player is beratted by constant connection closings, flow breaking 'host migration', and generally high pings ontop of rampent hackers and exploiters. this means that the diffrence between a good game and a bad game is mearly luck at times.
ontop of this, the CoD form of play in my point of view is mindless.
Because you have no natural map orrientation or designation of 'Mine' and 'Yours' the game will always naturally devolve into meager fragfests, spawn camping, and lone-wolfing. things like "team work", "communication", and "working Together" go straight out the window as in most matches even acknowledging your teams existance is optional to most all players.
this mechanic is largely supported by the 'Kill Streak!' reward system which supplies you powerful support abilities for simply getting a lot of kills with out dying.
to most players this makes the game feel more 'immature' as the only communication you'll ever hear is taunts, claims of victory, or spews of hatred and the only team work you'll see is in the form of people getting in your way to try and get more kills thinking that they can do better sniping out of the window you're shooting from.
in all honosty, the reason MW2 garners so much ire is because it is a QuakeDM style game... and that isn't modern war style combat.