Vista - Synchronize address books

Has anyone discovered a way to synchronize the new Windows Live Contacts with
the Windows Address Book in wab format?

Windows Live Contacts may be exported as csv but not wab. If one does
import the exported csv list from Windows Live into the Windows Address Book,
there will no longer be any group listings.

I need to keep a synchronized wab file (or its equivalent) for backup
purposes. A wab file may be imported into Windows Live Contacts, but not
eported from it.