"Simon -- the depth of your answer prompts long and expansive responses but I will not go there. Instead one more interesting layer is the opportunity for users to also participate in a marketplace -- such as being able to post in a gemeral database products, services, companies, organizatons, jobs etc. This is not to muddy waters but rather to consolidate experiences. Maybe there could be an option that allows you to select whether you want a "main" catalgory listing to be part of a marketplace -- which would then lead to a listing profile. Looking forward to talking to you."
