The Walking Dead has really good writing as evidenced by it's wild popularity and adaptation on AMC. Preacher is even better and is getting an adaptation in either late 2015 or 2016. Fables had a television adaptation in the works and got bounced around from NBC to ABC but it looks dead in the water; so it will be a while before the masses hear about this one.
People said there would never be a good comic book movie and then Christopher Nolan made The Dark Knight, Joss Whedon made Avengers, Sam Mendes made Road to Perdition, and David Cronenberg made A History of Violence. Comic books are just a medium like any other that require a good serious artist to bring out their potential. There's a reason why so many Alan Moore graphic novels have been turned into films like Watchmen. The man knows how to write. Then there's all that Indy stuff that's a little more artsy and gets some hipster cred like Maus, Persepolis, Ghost World, Epileptic, Palestine, etc. They tend to be more serious, lack action, are more naturalistic, and are about regular people, but I don't think they are actually any better. They are just giving people what they already expect from their art. There is a very prudish streak running through our culture that thinks art shouldn't ever be fun.