From the publisher announcement:
World of Dungeons is a complete short roleplaying game that answers the question "If Dungeon World was the latest version of a classic roleplaying game, what would the original look like?"
The game text claims a copyright of 1979...but that is part of the joke, re-imagining Dungeon World as an old-school game. It was released in summer 2012 as a bonus to funders for the Dungeon World Kickstarter project.
Don’t Tell Me the Odds (Cat campaign ends, Offworlders(World of Dungeons) game begins); Comments on A&E