First, what you describe here isn’t some standard off the shelf OSM application ofcourse. So to get this to work someone has to do some coding.
Adding references to media like photo’s to nodes etc. is already done to facilitate photo mapping. For that you would also geotag those media files.
Wikitravel is a service that does something that is quite similar to what you describe and is (starting to) using OSM for their travel books.
