This should come as no surprise given The Walking Dead's consistently stellar ratings over the past three years, but the zombie TV series -- currently in midseason hiatus -- has been renewed for a fourth season. Interestingly, though, Glen Mazzara, who's served as showrunner for the second and third seasons (following Frank Darabont's controversial departure), won't be back. The official word from AMC is that "both parties acknowledge that there is a difference of opinion about where the show should go moving forward." I don't normally care a whole lot about who the showrunner of a given series is, but The Walking Dead is one of the rare shows that has improved in quality over its first three seasons, so the fact that the show won't be going in the direction the person who oversaw such improvement envisions is a bit troubling. Still, that won't prevent me from eagerly anticipating Season 4 next fall.