Left 4 Dead 2 PC demo. These error messages are meant to appear after a player has been kicked from an online multiplayer match after failing to load a DLC map that the match host has selected for play. These disabled messages seem to indicate the names of what many now believe to be two DLC releases planned for the future: The "Miracle Pack" and the "Apocalyptic Pack."
Frankly, we think the game's already got its fair share of the Apocalypse, not to mention plenty of miracles, which is the only way we can explain how four people can survive continuous encounters with a city's worth of the walking dead. Still, we've contacted Valve to see if these two messages are a sign of more disastrous -- or miraculous -- things to come.