Google recently [released new vector cartography for their mobile maps](http://googlemobile.blogspot.com/2010/12/under-hood-of-google-maps-50-for.html). I'm curious if anyone here has any insight into the wire format they use for transmission? I've experimented with a few formats over the years, including [bencode](http://en.wikipedia.org/wiki/Bencode), [bson](http://bsonspec.org), variants of [WKT](http://en.wikipedia.org/wiki/Well-known_text) and [WKB](http://edndoc.esri.com/arcsde/9.0/general_topics/wkb_representation.htm), and gzipped, limited-precision [geojson](http://geojson.org) which I've found to be the best trade-off in comprehensibility and file size. I'd love to know what Google decided on, but I don't have an Android device to test with.