[natevw]

Years ago I wrestled against similar problems trying to make a completely visual map-based photo organizer, with only partial success: http://calftrail.com/mercatalog.html

So I can tell you that what Jason Davies has been doing in this realm recently is 1) really hard, 2) really legit and 3) really exciting. While Mercator was a great choice for tile maps due to its local properties, at medium and global scales it'd rarely be one's first choice.

Now, it doesn't have to be.