The argument that they will know which services not to use is nonsense. It's obvious to anyone with half a brain to not use things like Skype if you're doing so

The argument that they will know which services not to use is nonsense. It's obvious to anyone with half a brain to not use things like Skype if you're doing something that might attract the attention of the NSA, DHS, etc... even terrorists would know to use open source things like mumble that support encryption.