This was created in VS2008, should work just fine in VS2010.

Create a file called Books.xml in the executable folder.

Code:
<?xml version="1.0" encoding="utf-8"?>
<Root>
    <Titles>
        <Title Name="1">I love .NET</Title>
        <Title Name="2">I Love Delphi</Title>
    </Titles>
</Root>
Add this code

Code:
    Private Sub UpdateXmlItem()
        Dim Doc = XDocument.Load("Books.xml")
        Dim query = From items In Doc...<Title> Where items.@Name = "2"

        If query.Value = "Bye Bye Delphi" Then
            Console.WriteLine("You already said good bye")
        Else
            Console.WriteLine(query.Value)
            query.Value = "Bye Bye Delphi"

            Console.WriteLine(query.Value)
            Doc.Save("Books.xml")
        End If

    End Sub