I started reading the Ex-Heroes series because I have a geeky affection for zombies and superheroes, but Peter Clines is growing on me. The second book was a little better than the first, and the third book, while more of the same story-wise, continues to improve. It's still just a comic book in novel form, but like any ongoing series, if you stick with it you start to get attached to the characters and conversant with the continuity.
The heroes guarding the walled enclave of Los Angeles, surrounded by several hundred thousand "Exes," or zombies, ended the last book with a new arch-enemy: Legion, a superhuman who has the power to spread his consciousness among an ever-growing number of zombies and control them. In Ex-Communication, Legion continues to try to get at the survivors, but then a new Big Bad appears. St. George, Captain Freedom, Stealth, Cerberus, and Zap have to defeat an honest-to-God demon lord from hell.
The addition of actual magic into the Ex-Heroes' cosmology does it no great damage; it was already a comic book world. St. George continues to be the Superman of the series, and Stealth (now his girlfriend), the Batman. Zap is the Green Lantern, Cerberus is Iron (Wo)Man, and Captain Freedom... well, guess.
Clines spins a fun yarn, and it's about as consistent and coherent as a superhero/zombie novel can be. There are the usual twists, reveals, a little more worldbuilding, and some clever power stunts, but at this point the books are just new installments for fans of the series. Hopefully Clines will expand this universe and stretch out a little before it gets stale.