I have some contacts I wanted to share with other people so I figured let’s put them into Address Book Server on my Snow Leopard Server. I moved the group on to the server and everything was great. Contacts show up in Address Book on my macbook.
I synch my iPhone as usual. Next day I get a call from a familiar number but no name (I can’t remember phone numbers if my life dependent on it)! I check the contacts on my iPhone and none of the ones I moved are there!
After much fiddling and googling it turns out it doesn’t work! That doesn’t make any sense. How could Apple fail at something so basic? I imagine they want the iPhone to sync remotely to Address Book Server much like iCal and mail. Reasonable philosophy but it doesn’t do that! In the interim, I’d expect iTunes to be able to sync — after all, it’s in your address book. Not only that, they already handle Google sync using CardDAV, right? So why isn’t it in iTunes until they get it working on the iPhone!
From ForkBombr:

Sadly, this isn’t the case. Address Book Server works beautifully between Macs. It’s fast and reliable. However, the iPhone OS doesn’t support CardDAV, the technology behind Address Book Server, meaning these contacts cannot be synced over the air to an iPhone like iCal or Mail data.

And the relevant discussion:

ABS does not sync OTA or have push changes. The iPhone supports LDAP access. This means you can lookup contct info stored in your WGM for users in your company. It does not support CardDAV.

ABS is Address Book Sync; OTA is over-the-air; WGM is Work Group Manager (aka Apple’s LDAP server); CardDAV is how to share contact information.