Google recommends this utility for transforming an OS X Address book into the (yuch) CSV format Gmail can handle: A to G The easy way to get your Mac OS X address book into Gmail. This is one possible path on the way to using Google's ActiveSync implementation to sync contacts from iPhone to Google and gSyncIt to get them from Outlook to Google.
I'm approaching the problem of integrating my work, Gmail and OS X contacts with great care. It feels like juggling antimatter -- the data models are very different. There's a lot of potential arrow-of-time entropy risk -- data loss that can't be reversed.
One big confounder is the absurd persistence of CSV as a format for moving data around. That's was nice in 1970s. We should be using an XML transaction that ought to at least preserve line feeds in text notes. Unfortunately we should also be using object-oriented personal databases too, but the last of those died in the 1990s. (Anyone remember "Arrange" for MacOS?)