ContactsSyncer is your swiss army knife when it comes to dealing with your contacts data.
It imports contacts from :
OS X address book (contacts.app)
MS Outlook
vCards
Gmail
XING
Yahoo
Twitter
....displays them in a list, shows differences to the data in your contacts.app or MS Outlook, lets you change the data and finally exports them into either
OS X address book (contacts.app)
MS Outlook
MS Excel (including pictures!)
CSV
vCard
It will update present contacts (checks for the first and last name) to avoid duplicates in both contacts.app and MS Outlook.
Ever wanted to import multiple vCards into Outlook? See all of your contacts in a sortable list view? Here you go!