There is a new very interesting OpenERP Module which imports OpenERP data into Google Map.
This module creates a .kml file with all partners and partner turnover data which could be imported into google maps => simple and really interesting.
http://openerp-team.blogspot.com/2009/06/open-erp-integration-with-google-map.html
Two questions :
- Who is the owner of the data ?
- Is it really a good idea to put financial data (which should be kept secret) into google map ?
The best solution would be to create a MapFish project and import kml data into mapfish 
