I've done several tests and it doesn't seem like the User Bookmarks created on 7.52 will transfer once we migrate both client and server on QV9.00. Document bookmarks followed with no problem.
My tests are not totally conclusive because we run two server, prod is on 7.52 and test is on QV 9 and I know the XML files keep the application UNC path within. But even by tweaking the XML file to match the test server they are not available when I go in.
So I would like to know if other people who upgraded from version 7 to 8 or 9 have done anything in order to avoid recreating their user bookmarks manually.