No - it's not about people coming out as Church of England adherents. emergent is a term that is used by people who are looking for new ways to be church that retains the best of what has been, but reshapes for the future.
Anglimergent is a new site, which works on a social networking basis, for Anglicans looking to the future. I have signed up, and I'll keep you posted if it proves useful.
The platform it used for social networking is called Ning - you can create a social network for a particular grouping. It's less swamped by stuff than facebook, but obviously doesn't have the universality.