如何避免建造围墙花园？

Some friends and I have had an idea for a website and have started working on it. It will rely on people contributing to a shared knowledgebase, and people will also be able to create personal profiles with reasonable amounts of data. We intend people should be able to leverage their content on other sites (e.g.: flickr, youtube) when building their profile on our site.Some friends and I have had an idea for a websi