It is too chaotic but I can see you taking this in different directions. You need a way to direct the flow, potentially even in a useful direction (I am thinking Yahoo/Mahalo Answers), or just like a trending topics feature in which different worlds are based on tags.
Another thing you could do is to have a reset or form a new world every few minutes. This way there is a new slate.
What you will probably need to end up doing in order to monetize this idea is to build a site around it. User profiles, trending topics, different links, regional worlds, answers, /random/, and /ANSI art/ (read: penises)