You've probably already read about this week's release of Google Earth 5.0 and its exciting new features, including Historical Imagery, Touring, Ocean, and Mars. As is usually the case for new features in Earth, we wanted to add representations for some of them to KML. In the past this was done by simply adding new elements to the KML specification. But that's no longer an option for us, since KML is no longer controlled by Google, having been released as an open standard by the Open Geospatial Consortium.
So what's an application provider to do? Fortunately, both Google and the OGC had the foresight to anticipate that innovation would continue to drive the standard forward, so OGC KML includes a standardized mechanism that enables any group to extend KML within their own XML namespace. Google Earth 5.0 uses this extension mechanism to add to KML in a standards-compliant way. We've also added some new documentation to guide you in understanding these new KML constructs:
For those who are interested in precise XML validation of the new elements, please see Google's new KML 2.2 extensions XSD, which is the formal standards-compliant description of their syntax.
As always, you can find out more information or ask questions in the KML Developer Forum.
Give us feedback in our Product Forums.