The Microformats community is working on a new standard for signing up for Social Networks.
Instead of using OpenID, which it seems is nothing more than saying that you control a URL on a remote server with your name on it (there are no major standardized information transferred, etc). Social Network Portability would take the types of things that you normally type into registration forms: name, email, birthday, URL, friends, notifications, privacy preferences, blocking negative people, etc." and place that into a standardized file as an extended hCard+XFN file that you can automatically import over from other sites you've already signed up for. That's as far as the brainstorming has gone so far, but I would think that would raise some privacy concerns. Personally I'd rather the file be something that you can keep on your desktop and upload to a site as you please.
In any case, the discussion on how to form the new standard can be found over at Microformats.org. This approach might be good for future Vanilla 2 strategies. Only time will tell.