I’m not a programmer, but what this means as a practical matter is that the GeoRSS standard gets a big boost. Developers and mashups builders can now use a range of formats to add data layers to Google Maps and their sites using the Maps API. And it also means that there will be more geo-data on maps and on the internet generally in the future.
Google Maps and Google Earth (and maybe Coop and Google Custom Search Engines) are where Google is building its social media franchise. More on that for a longer post for the future. But adding this new support is another sign of how the social space is being allowed to come into the mapping space.