James,

This is wonderful! Any chance that you could split these into two server requests, one for the NASA image layer and one for DEMIS? That way a user could select the one of interest (in my case, DEMIS shaded relief) and not have it overlayed by the other...

Perhaps a server selection string, like is used in the Flikr network link:

http://www.geobloggers.com/makeXML.cfm

for the first one, and,

http://www.geobloggers.com/makeXML.cfm?geLatest=true

for the second.

Something like:

http://www.geovista.psu.edu/kml/kml2wms.jsp?database=DEMIS
http://www.geovista.psu.edu/kml/kml2wms.jsp?database=NASA

or some such.