In just 2 more days, I will finally have Left 4 Dead in my possession.  Soon I will be annihilating wave after wave of the Infected, all the while covering my companions as they do the same.  You can't just run into a horde of zombies with a shotgun and expect an easy killing spree.  No, in this game you must utilize your  teammates any way you can, be it providing them with health after being severely injured, or assisting them when they are pinned down by the infected so as to spare them the gruesome transformation of becoming a flesh eating predator.  Hopefully, this mechanic will be used to its fullest, and in turn provide a high replay value which will keep players coming back to not only play their favorite levels again and again but to try and out do their last run through by picking a more challenging difficulty, which will make teamwork a necessity in order to survive.  Until the day comes when I can finally live out my Dawn of the Dead fantasies, I will have to be content with pondering the creepiness and suspense of the oncoming infected as they move in to satisfy their hunger.