Vista - xpath XML from "GPMgmt.GPM" report

Has anyone had any luck on running an xPath query against the XML
report generated from the GPMgmt.GPM GenerateReportToFile method?

Even if I try something as simple as this wich should echo the name of
the policy:

xmlXPath = "/a:GPO/b:Name"
xmlFile = "C:\Domain_Policy.XML"
set xmlDoc = CreateObject("Msxml2.DOMDocument.4.0")
xmlDoc.PreserveWhitespace = True
xmlDoc.async = False
xmlDoc.Property "SelectionNamespaces","xmlns:a='http://
www.microsoft.com/GroupPolicy/Settings' xmlns:b='http://
www.microsoft.com/GroupPolicy/Settings'"
xmlDoc.load(xmlFile)
set xmlNodes = xmlDoc.SelectNodes(xmlXPath)
For i = 0 to xmlNodes.Length-1
wscript.echo xmlNodes.Item(i).Text
Next

I get nothing returned

What I really want to try to do is to lisst all of the assigned
applications from each of the group policies in the domain.