AT&T CallVantage customers who are not officially where the E911 service is located (i.e. those that lie) are getting served with disconnect notices. I hear the same thing is happening with some AIM PhoneLine customers as well from the AOL exec on the project.
This is really about playing it safe and minimizing risk for future law suits. In the near term the pain will be to the consumers, but with enough options for VoIP these days, from services people will be able to find service.