For those of you using the latest version of iTunes and an iPhone, you may have noticed the "Sync Google Contacts" option in the iPhone sync settings...

Can someone tell me exactly how this works, because Address Book now also has the option to "Sync Google Contacts"... if Address Book is already set to sync with Google, what is the point of setting it through iTunes as well? Is this for people who do not use Address Book?

I'd really appreciate it if someone can help me configure the following... My main contact list is in Address Book.. I sync it with my iPhone all the time... but it would be nice to be able to access my contacts via the Gmail interface as well... how should I go about configuring this so that Address Book is the central contacts manager?