I'll let Yahoo describe it:
Our purpose in creating the Internet Location Platform is to provide the Yahoo! Geographic Developer Community with the vocabulary and grammar to describe the world's geography in an unequivocal, permanent, and language-neutral manner.
This looks very interesting. Currently, it is possible to use the geocoding service of Google Maps, or a site such as geonames.org (we use both for Nelso). However, the new Yahoo service is much more sophisticated and might be easier to use.
I'm going to play around with it a bit and post more on it later.