What do the people pushing "GeoWeb" at Google, a company founded on links, think about geographic data and web architecture? It's not so clear. I've been waiting for a post like this from Mano Marks:
Is that the nature of geographic data? Or have we just not found the true linkability of it? I tend to think it's the former. Geographic data is heirarchical, it is ontological, it is content rich, it is combinable. It is linkable through common ontologies. But geographic data doesn't lend itself to easy linking in the same way. It's the nature of structured data, it must relate to a structure. Ontologies are almost the antithesis of linkablity outside the domain.
I think he's overlooking another form of linking in KML: the combination of "network links" and "regions". In practice, KML applications use this to implement pyramids of increasing resolution for data from a single domain, but one should be able to network link in the same way to KML applications from other domains that best serve a particular view. It might even be feasible to implement an agent that would crawl network links. Some changes to the network link to make it more like other web links would probably help. Linked geographic data  could be right here under our noses, in KML, already.
 Yes, I know I'm abusing the linked data brand.