I suppose that you will add the sync ability when you can. I don't want it. I don't want to give all my phonebook to whatsapp inc, so for me is perfect to add contacts myself and not sync them.

Please please please please, if you add sync ability, could you add an option to choice not to syncing with phonebook?

Now I need to register myself with a non-existent mobile number so I won't give any data to whatsapp (apart from numbers of contacts they already have).