The distribution is pretty small as they are lat/lon coordinates
that have been mapped to positive integers. Most of them are near
each other and the queries are in a relatively small range, e.g.
(geo_lon:[5752427 5781706] AND geo_lat:[13750592 13763600]).
I know this is not the question you asked... but for geographic stuff,
you may want to consider looking at local lucene:
http://sourceforge.net/projects/locallucene/
This indexes lat/lon with a bunch of tiers. I have had good luck with
it so far.
ryan
