I still need convincing that The Walking Dead' is anything more than a hackneyed apocalyptic melodrama with borscht-like guts spilling out all over the place.
The show's main problem is its lack of compelling characters. It isn't a question of whether or not they're "likable." They are likable. That's the problem, actually - they're likable to a fault.
Six million zombiephiles watched the finale of the first season and those 6 million will not want to miss Sunday's opener, which is excellent and appropriately disgusting. The larger concern is the future.
There is so little depth on display that if you replaced every single member of the cast with an animal you'd have essentially the same show. You'd probably have a better one.