I'm far from finishing the game (I think, at least) but so far I'm greatly enjoying this episode as well! It seems that with every new episode all aspects of the game improve a little, including the puzzles, the writing, the characters, the voicing, the animation and even the game engine.
The only areas that could use some improvements are in the graphics/animation department; the lack of lip-synching makes dialogs less engaging than they could be, and many of the models and locations could be a bit more detailed and dynamic. For example, there is a queue in front of the Zombie Factory suggesting the place will be crowded, but once you get inside there are only two raving zombies inside! I think there is a joke about fire regulations that tries to explain it, but nevertheless it detracts somewhat from the atmosphere since the place feels mostly empty.
But these are minor things, and in general my experience is pretty positive. Kudos to the Telltale team!