Facebook Platform supports OAuth as a standard authentication protocol for 3rd party apps. It also provides APIs that developers can use to export data users have entered into facebook (with the user's permission, of course). What do you think is missing in Facebook's support for data portability?
Most importantly, though, a clear change (or clear guidelines) to the Terms Of Service which would guarantee that moving your data to a competing service would not result in cancellation of the account or deletion of the new service's API key.
As for a distributed protocol, take a look at the functionality in Appleseed's QuickSocial and StatusNet for an idea of what a distributed protocol entails. I should be able to login to facebook with an external identity, and add someone as a friend on facebook, without having an actual facebook account.
If Facebook is interested in these things, you can have some representatives join the Federated Social Web mailing list, and you can support the W3C working group on federated social networking, as well as supporting the Data Portability Project.
EDIT: and a full realtime read/write XMPP-style interface for all the data going in/out of my profile please! :)