Ok, I'm interested in this and don't have the time to work on it, so I'm going to try invoking the mystical power of the LazyWeb to get it done:

The idea is that someone creates an XML namespace for geoURL data with a couple elements that can be added to an SMBMeta file (see mine here). Although the SMBMeta format already has location and address information, GeoURL info would be kinda cool too.

update: Dan wrote to say that enough people have mentioned this that they're likely to add a <coordinates> field to SMBMeta. <mr burns>EEeexceellent</mr burns>.