First is that I can actually see what is going on. Too many shows, horror shows in particular, but action flicks are right there with 'em, do crap at night, or in a dark building. I suspect they do this for the creepy what-lies-in-the-dark factor, but somewhere in the back of my head I think they do it because they can't afford to choreograph it right, do special affects or the actor has no idea how to wield a sword. All legitimate reason to do stuff in the dark, and its fine (no criticism intended) but from a viewer's perspective I can't see what the heck is going on. Sometimes is like bright lights and faces and a black tv screen.
The Walkind Dead does that occassionally, but as often as not, I can see what is happening, because the zombies, the walkers, are walking in the daylight. Its refreshing.
Secondly, I'm pretty sure when the apocalypse happens, unless its the sun novaing, that there will still be daylight. So its cool to see an apocalyptic landscape in which people are moving through a normal natural environment. Its not all dark and dreary, cloudy, and goth. Its just the earth and things have changed for us.
Its all very cool.
The apocalypse that is. And the Walking Dead.