User blog comment:TkaiaWolf/Life-Consuming Haters/@comment-4148373-20120926161759

I'm wondering about this delay: I seriously suspect they are either updating the map with new tools from the update or their mods are really, really bugged out by the update.

I think they're updating the map. I just looked at the amount of stuff added in 1.3. They're probably adding in tripwires, redesigning buildings to use the new wood colors or upside-down stairs, stuff like that. And that's assuming they don't try to use a snapshot for the new stuff that added, like night-vision potions or invisibility potions.