“The only step missing is for either Flickr to output KML natively … ”

The bbox being used as a parameter on the Flickr API was designed from the start to be the same as the bbox from Google Earth. Just so it’d be possible at some point to point Google Earth directly at the Flickr backend (with extra optional parameters passed if you wanted).

This makes sense, as we most certainly have more processing power to handle the request load than someone else having to use their API key and code to convert our XML format to KML.

The reason why it hasn’t happened yet is just because we’ve been working on other things … and need to check that we indeed can handle the load

I haven’t even looked into the politics of (Flickr!