i dont understand how people are complaining about this show, especially this season. This season has been really action packed. As i said before, you cant have a show just about killing zombies every 2 seconds, because that WOULD lead to "flat characters" (as someone called them above). Personally ive loved every episode. Even the second season which was very low on action i felt was incredible. That entire season was spent on character development so that you actually feel some sort of connection with everyone (well, everyone except t-dog... 2 lines all season) so that they arent all just cannon fodder.
Season 2 was FILLED with tension, especially between rick, shane, and lori. Im going to be as vague as possible here to avoid spoilers, but the conversation Lori has with rick in the tent about Shane in season 2... that was an amazing scene.
The Walking Dead isnt a show about zombies, its about people trying to survive. The zombie apocalypse is just the backdrop for the story, and the zombies are really just there in a supporting role.
You dont need constant action for something to be incredible. Just look at any Tarantino movie... he always has long dialogue scenes but they are amazing.
Case and point
http://youtu.be/sPq-QILGOAY