It is really annoying have multiple sources of contacts on icloud such as facebook, exchange, your iphone/mac.
If you find yourself looking at your address book contacts and you can't decide which one is the right one between 3 or 4 duplicates, this suits for you:
- Go to your address book.
- On the top menu click on card menu
- Select "Look for duplicates"
After scanning your contact list, the app will ask you what do you want to do with the contacts (merge?)