Philip Holmstrand, who works at the City of Portland (makers of great mashups) contributed some suggestions to the Google Earth community bulletin board in a post entitled Two steps from becoming the next web browser!
What are the two features Google Earth is missing right now, according to Philip?
– The ability to link dynamically to a KML from within another KML, without using a browser as an intermediate step.
– The ability to manipulate navigation around the globe beyond just the loading phase. This could be done by giving us the ability to dynamically load/unload KML rather than just refreshing based on NetworkLinks
Re the first point: We can already link to an HTML URL from within Google Earth. We can link to a KML file from within an HTML browser. But what Philip wants is the ability to fetch and render KML files from links in KML files. Just like how we click in on HTML links in HTML documents to fetch new HTML documents, in fact.
One possible solution is to use a universal <a> tag (something which I discussed here.) These could be used in both HTML browsers and GIS browsers like Google Earth. That way, HTML snippets would be highly portable, as text containing such <a> tags would work in either browser, or depending on preferences.