While I do consider Valve to be a very consistent developer in the vein of Bioware and Bethesda, the one thing the company doesn't do for me is have every franchise be something that I love to the core. While I'm a huge Team Fortress 2 fan and will defend any naysayers of Portal, stuff like the Half-Life series I just plain cannot get into. Sections go on longer than they should, the shooting is adequate but not exceptional (aside from the Gravity Gun of course) and I find it personally hard to care about a story where the most all-important figure in the entire thing (you) doesn't say one word. Which makes the Left 4 Dead games curious entries in that it's kind of in both camps: a game I really love but only in short bursts and even then, I still find things too gripe about. The core gameplay's still intact and I even prefer this game to the sequel but this game is quite fun but at a certain point, it feels like you've played it far longer than the content actually feels.
Game takes place 2 weeks after an infection starts turning people into ravenous mutants, some undergoing huge changes. You play as 4 survivors: Zoey, Francis, Bill and Louis as they make their way in each campaign (set up amusingly by a B-movie poster) and escape alive. And that's the game pretty much: pick level, make it through parts, reach a safehouse where you can stock up on ammo, medkits and change weaponry if you want and make it to the next. The action does feel slightly repetitive in that because there's only a small number of chapters, be prepared to re-see a lot of it, and it doesn't help the community now is kind of small so I hope you like the hospital level because you'll grow to love seeing it constantly.
You'll find some unique zombies to face and toy around with in Versus mode such as the Boomer which can either puke or explode its guts over people, making the swarm come in droves towards them. The smoker that can latch onto people with their tongues and let other zombies hit them, suspend them over high areas or smack them if they get close. Hunters hop on foes and can't be shaken off unless punched, shot off or the victim dies while the Tank and Witch are the most deadly, one is an all-powerful beast while the other can knock you flat out if you disturb her. It makes for some unique playing experiences when you faced with dealing with the various types, sometimes all at once. The horde itself is rather stupid but least they can get on my nerves now and then.
The main issue with Left 4 Dead is the small feeling found in its content. There's just simply not enough locations to play a game like this over and over, especially on consoles where you don't have the endless stream of mods on the PC version. Including all DLC, there's only 6 levels to pick from, each lasting I'd say 40 minutes to an hour depending on difficulty so the main draw becomes getting into a lobby and seeing how players will play, which is another issue the game has (though certainly not its fault). Rage quitters, people who shoot you instantly, randomly being put up to be voted off and other such nonsense can happen and happen a bit too much. This is a case where "it's better to play with friends" is really encouraged because along with Gears of War 2, I've never seen a worse community than Left 4 Dead's.
Is the game worth the purchase? Well if you asked me in 2008, then no. There wasn't enough chapters, versus mode was only on 2 maps and the DLC hadn't come yet but since the game be found for about 20 bucks now, then yeah it is. But be warned: most of either moved onto Left 4 Dead 2 or they're playing the PC version because the people that are left well...let's just say they don't help matters. The game's a blast but too much of a good thing can be a bad thing in this case.