Also should note I am getting this error:

[RPC Fault faultString="[MessagingError message='Destination
'http://www2.med.umich.edu/prmc/media/all.xml' either does not exist or the
destination has no channels defined (and the application does not define any
default channels.)']" faultCode="InvokeFailed" faultDetail="Couldn't establish
a connection to 'http://www2.med.umich.edu/prmc/media/all.xml'"]

You can see that the destination does exist and there is a channel

Examine my simplified code, which works, to see what I changed:

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
creationComplete="getXML.send()">
<mx:Script>
<![CDATA[
import mx.collections.XMLListCollection;
import flash.net.navigateToURL;
import flash.net.URLRequest;
import mx.rpc.events.ResultEvent;

[Bindable]
public var RSSFeed:XMLListCollection = new XMLListCollection();

public function resultHandler(e:ResultEvent):void {
var list:XMLList = new XMLList(e.result..item);
RSSFeed = new XMLListCollection(list);
}

public function openURL(event:MouseEvent):void {
var dgataGrid = event.currentTarget as DataGrid;
var str:String = dg.selectedItem.link;
navigateToURL(new URLRequest(str),"_blank");
}
]]>
</mx:Script>
<mx:HTTPService id="getXML"
url="http://www2.med.umich.edu/prmc/media/all.xml"
result="resultHandler(event)" resultFormat="e4x" useProxy="false"/>
<mxataGrid dataProvider="{RSSFeed}" id="feedsDG"
doubleClick="openURL(event);"
doubleClickEnabled="true">
<mx:columns>
<mxataGridColumn headerText="Title" dataField="title" width="200"/>
<mxataGridColumn headerText="Link" dataField="link" width="200"/>
</mx:columns>
</mxataGrid>
</mx:Application>

Here is how I might go about the same (based on Greg's code):



<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
creationComplete="getXML.send()">

<mx:HTTPService id="getXML"
url="http://www2.med.umich.edu/prmc/media/all.xml"
resultFormat="e4x"
useProxy="false"
result="RSSFeed.source=getXML.lastResult..item"
fault="mx.controls.Alert.show('\n\nXML data acquisition failed.\nTry
refreshing your browser.\n ','Data Error')" />

<mx:XMLListCollection id="RSSFeed" />

<mxataGrid id="feedsDG"
dataProvider="{RSSFeed}"
doubleClick="navigateToURL(new URLRequest(
feedsDG.selectedItem.link ), '_blank' );"
doubleClickEnabled="true">
<mx:columns>
<mxataGridColumn headerText="Title" dataField="title"
width="200"/>
<mxataGridColumn headerText="Link" dataField="link" width="200"/>
</mx:columns>
</mxataGrid>

</mx:Application>