The data we've loaded (flickr_data.kml) is from a third party source, but it's only fresh up to the point that we download it. Let's address the second point we came across previously:

Use 'live' data, and not download a KML file ourselves when we want new data

What we need to do is access the data in real time. To do this, we'll need to use a ProxyHost. This term is discussed in more detail in Chapter 9, but it's essentially a way to circumvent the cross domain request restraints of AJAX by calling on some server side script to make requests for us (acting as a proxy).