VB.NET: Select All Ids from Xml

[toytoy]

Say I have this Xml....

<Books>
<Book>
<Title ID ="1">
<Author>Hello</Author>
<Reference web = "www.reference.com" topic = "In thing">
</Title>
</Book>
<Book>
<Title ID = "2">
<Author>Thanks</Author>
<Reference web = "www.titlebook.com" topic = "Out thing">
</Title>
</Book>
</Books>

I know that..

'Get a list of books authored by Thanks
nodeList1 = root.SelectNodes("/Books/Book[Author=""Thanks""]")
'Get a book with a certain title:
xNode = root.SelectSingleNode("/Books/Book[@Title=""Book Title Here""]")

but how to select all the Ids..

Thanks