In terms of the show's long-standing postmortem show, The Talking Dead, this is not your average character death. First of all, whenever a major character dies on TWD, the actor usually shows up as a surprise guest to talk about their departure. Steven Yeun, who plays Glenn, does not show up in Sunday's episode.
What also struck us as weird was Chris Hardwick's language. He keeps saying things like, "Glenn appeared to be ripped apart," or "what seemed to be Glenn's intestines." To be fair, Hardwick makes it clear that he knows nothing about what's to come, but his doubt breeds our doubt.
Finally, Glenn actually isn't included in The Talking Dead's "In Memoriam" segment this week. It could be denial on their part. Or it could be something else.