The thing is, there is a difference between a slow burn and chasing it's own tail. Take the two other Sunday shows that I watch for example, Dexter and Boardwalk Empire. Both also use a slow burn story telling method. But the difference is, there is an actual payoff to the slow burn. At some point there needs to be a payoff. And I know that defenders will argue, "This show is about characters, not story!" or "There is no payoff to be had, everything is gone, it's just about surviving." And that is all fine and good, but it doesn't change the fact that this is a television show. It needs to tell some sort of story and resolution (then new stories and resolutions and so on). Even The Sopranos which was all about character, advanced their plot. This show needs to do the same.
This sums up my feelings on it very well:
http://popwatch.ew.com/2011/11/07/walking-dead-moving-too-slowly/