Our start-up site will use a listing of product/service categories. I want our site's community of members to decide what categories/subcategories get added, as well as, other aspects about each item. It's a wiki approach where individual small pieces of content come together to create a larger output, almost like wikipedia, except I want people with the highest reputation to be the ones that control the ultimate output.
So, I invision a solution that is kind of a combination of StackExcahnge's reputation-based governance and Wikipedia's approach to numerous members contributing different pieces of a larger product.
I have to imagine that this is already out there - built and ready to use.
What solutions are out there that I can use instead of building from scratch?
Who is already doing something like this (even if it's for something other than product categories)?
You could easily do this with MediaWiki or Drupal using just contributed modules
If i understand you idea correctly you want wiki with votes for wiki pages. AFAIK nobody doing it but you can implement it and this is fairly good idea.