The Web appears lifeless and static. This actually is wrong. There are many people around. There is plenty of life, but it is unfortunately hidden from users. Static neighborhoods, communities, MUDs and chat systems are used to provide places where people can meet.
People go there to meet others.
They can not meet on any page, in any place of the Web. Other objects are not visible via the Web's native mechanisms. This is the task of the dynamic neighborhood service. In the real world, the visible area is different from person to person. Everyone sees a different subset of the objects in the neighborhood, e.g. other people, things, pictures, etc.