At first this series seemed like an ordinary zombie comic. I said At first.
What makes this series unique, more so than any other zombie story ever told, is that its not just about the zombies.
This is a character driven story which at the same time incorporates the very real threat of living in apocalyptic world. At any moment someone will die, could be that guy who showed up for an issue or it could be the guy you've known for fifty. What I'm saying is that in regards to feeling "realistic" and having it in a zombie story: this is the best story you will ever find.
Don't just take it from me, look at the other reviews or just take a look at how damn well it is selling. The TPBs are always reprinting, there's a TV show, and they are reprinting the entire comic book series as "The Walking Dead weekly".
If you are not reading this series then you are seriously missing out.