Sync AddressBook with Plaxo universal address book.
Automatic synch between your Apple Address Book and you Plaxo Universal Address Book
Plaxo keeps your Outlook address book up-to-date. You choose which people you want to get updated contact information from. Their replies are automatically inserted into your address book. eWeek http://www.eweek.com/article2/0,4149,1234228,00.asp