Hi starting a new project - thread here
https://openacs.org/forums/message-view?message_id=85199 - some of the functionality might be related to this thread. We're in the very early stages but I am thinking about using the "knowledge base" in Oracle text (formerly known as intermedia) or at least part of it as a hierarchy of categories. This knowledge base is stored in a tree like structure (otherwise known as a taxonomy). I am also looking at letting users browse or search the taxonomy itself)or part of it) and to update it. They could register their preferences at various poiints in the taxonomy and also use the taxonomy tree to do Yahoo-like browse searching. There is also the concept of searching for content based on what the content is "about" which I am looking at. I'm sure this will return several categories for each piece of content. So we wouldn't have to actually store any categories with a piece of content - we could just generate them each time we searched...
...Now enough theory - have to see if any of this actually works...