I'm a Facebook Friend of Dan Patterson, and usually enjoy his comments about social media (particularly from his perspective as being part of the "old world" media). But I had never paid much attention to his Zombie Doom project before he posted a link to TechCrunch: Foursquare's Next Game: Choose Your Own Adventure (which is commenting on part of a podcast fromTheBigMoney) where he commented that this was what they were trying to do with Zombie Doom as well.
You can understand why I got interested.
But from what I can make out of both projects so far (not much, to be honest), they both sound like they're making an adventure and not an addventure, which is surprising considering both should have an understanding of user created content, not just user participatorycontent. And certainly when it comes to Foursquare, they want to keep a very tight control over their brand and the quality of what they provide, so an addventure could be a challenge for them.
I once wrote a text-based adventure game (zork style thing) that was set in Paris (it was for a French class... so sue me). You started with a clue that would send you to a location in the city, and went from clue to clue until you found the final prize. I can almost see a geo-based treasure hunt of this sort being something that can be created by users, but still "run" by Foursquare.
A geoAddventure would take this one step further. Maybe even several steps. Not just clues at each point, but multiple clues. And getting to an empty location (once you figured out that location) lets you... set clues to a new place? I dunno... still seems like there might be serious quality control issues at play. And how do you keep that within any sort of a story line? We had enough trouble with straight text addventuring!
But if you don't... I can see users solving the adventure quickly... and then getting bored with the new feature.