I found an interesting blog on VoIP and 911, by Richard Edge. He points out that the FCC ruling has a description of a VoIP provider that clearly includes Skype, implying that the FCC 911 ruling should also apply to Skype, and that the other VoIP vendors might take action against Skype for not complying. However, a more recent blog by Richard also includes the comment that 911 only needs to apply if the service can 'Provide, or enable use of, traditional CPE or CPE that, like traditional CPE, is always on and has dial tone'. Since Skype is clearly a service that is only one when the user wants it to be (switches on their computer and runs the skype client) it might be exempt from 911. I personally think that this is the reason why Skype has never gone the ATA route, and only targets people actually running/using PC's. As soon as they provide a Skype phone that does not need to connect to a PC (ie. runs the client on the phone, and connects with Wifi, for example), they would open themselves to possible 911 hassles (and other regulatory hassles).