FB blue is there, and the video from Daniel on the main WPC page shows how it plugs into the Me tile which was still there on his build of WP8.1 (though it was obviously an older build that he had).
Link please?
Facebook integration is still there but was changed as it integrates with the facebook app now and perhaps with the facebook messenger.
so we still have to use the Microsoft app and not a Facebook developed app?
I doubt it will be ALL new. I mean, Facebook has a mobile app vision, and iphone, android, and windows phone all have the exact same app. If I were to guess, I'd say the current app will just be updated to compatibility with 8.1 and some code changes to link in with the new APIs for messaging/integration/cortana.