In a collaborative environment,it will naturally happen that two or more people enter geographic identities which are the same, overlap, or are related in some way. A collaorative system should provide ways to detect when this has occurred and provide ways to resolve or help users deal with it.
I can see three basic scenarios (maybe there are more) each with a different detection and resolution mechanism.
a) simple duplication. Person A enters a brief and sketchy entry for "Rome" without noticing that person B already has an excellent entry for "Rome". Resolution- after brief discussion, person B agrees to use or point to person B's entry and deletes their own.
b) parallel development. Several people have added overlapping information about a location; no one entry is superior to the others and several entries should be merged. This requires a means of detection, the facility for comments on other peoples entries (there, but seems to be disabled by default) and possibly other collaborative discussion tools (wiki,etc) to allow a collaboratively produced, jointly authored entry tobe created which subsumes the earlier ones.
c) relationship. Person C enters "Vaison La Romaine" and person D enters "Room C3, Villa of the Peristyle, Vaison La Romaine". There is a need for both entries, but the relationship of one to the other needs to be discoverable ("see also" or "part of" relationships). Same for non-point entries, such as districts, provinces, etc.
