[ResearchIdea] Social Text Landmarks

I thought of a kind of notes linked to a GPS point like in GeoNotes. When someone enter a zone, he receives one or two notes. The new thing here (compared to all those location-linked information system) would be that people only receive messages from their social networks (described for instance by a foaf.rdf file). We can imagine a rating system of the messages in order to get only the most interesting messages.