Re: Alternative to Facebook
It depends on your definition of “near future”. Since all authentication is handled by WordPress, not BuddyPress, this project is truly a WordPress-specific feature. We are forming a group to work on this issue and also discuss the possibilities of implementing Semantic Web and / or Open Stack protocols in BuddyPress.
But, this will not be a core WP feature–at least not in the near term. I imagine that we will let the WP 3.0 series work out any new issues once that series is released. So, sometime around the WP 3.1 or 3.2 public release might be a reasonable target for releasing a WebID plugin for WP.
Do you have any specific interest and / or experience with WebIDs?