I have a site with company profiles. I already have a sitemap.xml

However, now I'm reading on KML geo sitemaps: http://www.seomoz.org/blog/understand-and-rock-the-google-venice-update

I wondered how that may apply to a site with company profiles. Do I place 1 large KML file showing all the locations of businesses in the KML format? Or do I need to make that more specific? locatins-in-LA.kml for example?

And what is the relationship between a kml file and a sitemap.xml? It seems that I need to have a reference to the kml files that should be included in the sitemap.xml, but if that is the case, I don't know how.

Help! :)