Galaxywomun , my best guess is that this site (as a free site) is pretty much 'member-powered' , with many active (& formerly active) members .
As far as promotion , the ones that happen here are related to the # of posts a member creates .... i.e.- 'new member', 'hero member' , etc. , as well as 'promotion' in the eyes of other members , depending on the expertise/interest/accuracy of research a member shares here .