I just upgraded to Mavericks. Here is what I find shocking...
1. Mavericks will NOT sync Apple Contacts with Google Contacts and vice-versa.
2. During the upgrade, Mavericks linked some of my Apple Contact cards with Google Contacts, but not all of them. It need to be clarified that linking is not syncing. Worse, it corrupted data, and deleted some of the contacts on Google Contacts.
3. Similarly, Apple Contacts will not sync with Linkedin or Facebook Contacts.
4. When I contacted Apple, Level 1 support had not idea and assumed that adding a Google Account with automatically sync Apple Contacts with Google Contacts as it did in OS Mountain Lion. Level 2 support did not have much of an idea either, but called me this morning to say that the matter has been escalated, and confirmed that OS X Maverick does NOT sync Apple Contacts with Google Contacts.
CAUTION before upgrading to Mavericks:
5. Your Google Contacts / Android devices will not be updated by Apple Contacts, and vice-versa.
6. Your Facebook / Linkedin contats will not be updated by Apple Contacts, and vice-versa.
7. Before upgrade, ensure that your Mountain Lion or earlier address book in synced with Google Contacts.
8. After upgrade, go to Contacts > Preferences > General > Default Account, and choose your Google Account as your default account. You will now add New Contact (or update existing Google Contacts) in Google Contacts, which your android devices can sync with. You will also see your Google Contacts in Apple Contacts. However, Apple Contacts will NOT sync with Google Contacts and vice-versa.
Welcome to Mavericks...