I love the simplicity. We started with a very similar premise around collaborative list-building for travel when we created http://www.planapple.com http://www

I love the simplicity. We started with a very similar premise around collaborative list-building for travel when we created http://www.planapple.com http://www.planapple.com. (We're a couple years of features and iterations into it now, so it's grown beyond simple lists in both functionality and UI complexity.) FWIW, we've had trouble getting any traction on public list sharing, and we've tried a handful of different approaches. Our users are very happy to collaborate in small groups, but that's where it ends. Some stumbling blocks: 1. You'll need a critical mass of really good, yet somewhat mainstream, lists to attract people who will fork an existing list. 2. Until you have that, you'll attract mainly people who want to build their own lists from scratch and enjoy/are willing to put "a lot of work" into their planning. And that's fine (it's who we're getting now) -- but that kind of people tend to build highly-customized lists that aren't likely to appeal to most other users. 3. Mainstream users aren't that willing to spend effort searching through a bunch of different lists to find one that matches their interests. (Though if you have ideas for an algorithm that can figure out my list for London on a backpacker's budget won't appeal to your interest in a luxury London holiday, let me know!) 4. In practice (for travel planning, at least), the lists tend to contain a mixture of general-interest info plus specific details (like my hotel confirmation number) -- which means they need filtering before they could be made public (and people don't want to spend time on filtering). But I definitely don't mean to discourage you -- just wanted to pass along some of what we've learned. Thanks for sharing.