Please consider adding support for the Portable Contacts API

"PoCo" is an effort to standardize address books APIs between service providers. It's not that we need "yet another" address book API, but this one intends to harmonize many of the differences with previous approaches (as we did with OAuth) and provides a modern mechanism for interacting with contact resources. It also requires OAuth, so you're well ahead of the curve!

http://portablecontacts.net
http://portablecontacts.net/draft-spe...

Please take a look!