I was in Mackay last week and ran into a problem where it appeared shadow copy/restore wasn't working in Windows Vista during a presentation.  

After the presentation i played with shadow copy for a couple of seconds and realized the culprit was the fact i using search to open the file -and how i was attempting to restore a previous version.  What i hadn't realized was that Windows Vista had created a shortcut (link) to the my document and THIS is what search had been finding.

Which works fine for opening files but no so good for restoring content in the original file when the link is being updated.

Of course the "solution" is to restore the file by clicking the original file not the link.