Is it possible to setup a mac mini as a central photo repository and have all the tagging and extra info follow to the other computers on the network? Or would each computer have to access iPhoto on the mini or have their own index?
With the way that iPhoto is built it would be quite difficult to share the library across computers. We have had some success with having an aperture library sit on a network share and have multiple installs access that library but not simultaneously. If you want central I'd suggest something like picasa web from google. That way all machines can access the existing stuff and also contribute to the main repository.