Open protocols and interop seem like a very good goal to aim for. I'm curious how geographical lines would work for Facebook -- would you end up with one Facebook per country? And would we still end up in a situation where you need to have a Facebook account to participate in things like Marketplace or community groups?

Personally I would want to be able to host my own tiny Facebook instance that I control. Ideally I could even invite friends and family to share my ad-free self-hosted instance with a chronological newsfeed setup.